Haptic input devices

ABSTRACT

A haptic feedback touch control used to provide input to a computer. A touch input device includes a planar touch surface that provides position information to a computer based on a location of user contact. The computer can position a cursor in a displayed graphical environment based at least in part on the position information, or perform a different function. At least one actuator is also coupled to the touch input device and outputs a force to provide a haptic sensation to the user. The actuator can move the touchpad laterally, or a separate surface member can be actuated. A flat E-core actuator, piezoelectric actuator, or other types of actuators can be used to provide forces. The touch input device can include multiple different regions to control different computer functions.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of co-pending U.S. patentapplication Ser. No. 09/487,737, entitled “Haptic Feedback for Touchpadsand Other Touch Controls,” filed Jan. 19, 2000 by Rosenberg et al., andthis application claims the benefit of U.S. Provisional Application No.60/274,444, filed Mar. 9, 2001, entitled, “Haptic Interface for LaptopComputers and Other Portable Devices,” and which are incorporated hereinby reference in their entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to the interfacing with computerand mechanical devices by a user, and more particularly to devices usedto interface with computer systems and electronic devices and whichprovide haptic feedback to the user.

Humans interface with electronic and mechanical devices in a variety ofapplications, and the need for a more natural, easy-to-use, andinformative interface is a constant concern. In the context of thepresent invention, humans interface with computer devices for a varietyof applications. One such application is interacting withcomputer-generated environments such as games, simulations, andapplication programs. Computer input devices such as mice and trackballsare often used to control a cursor within a graphical environment andprovide input in these applications.

In some interface devices, force feedback or tactile feedback is alsoprovided to the user, collectively known herein as “haptic feedback.”Forexample, haptic versions of joysticks, mice, gamepads, steering wheels,or other types of devices can output forces to the user based on eventsor interactions occurring within the graphical environment, such as in agame or other application program.

In portable computer or electronic devices, such as laptop computers,mice typically too large a workspace to be practical. As a result, morecompact devices such as trackballs are often used. Currently, a morepopular device for portable computers are “touchpads,” which are smallrectangular, planar pads provided near the keyboard of the computer. Thetouchpad senses the location of a pointing object by any of a variety ofsensing technologies, such as capacitive sensors or pressure sensorsthat detect pressure applied to the touchpad. The user contacts thetouchpad most commonly with a fingertip and moves his or her finger onthe pad to move a cursor displayed in the graphical environment. Inother embodiments, the user can operate a stylus in conjunction with thetouchpad by pressing the stylus tip on the touchpad and moving thestylus.

One problem with existing touchpads is that there is no haptic feedbackprovided to the user. The user of a touchpad is therefore not able toexperience haptic sensations that assist and inform the user oftargeting and other control tasks within the graphical environment. Thetouchpads of the prior art also cannot take advantage of existinghaptic-enabled software run on the portable computer.

SUMMARY OF THE INVENTION

The present invention is directed to a haptic feedback planar touchcontrol used to provide input to a computer system. The control can be atouchpad provided on a portable computer, or can be a touch screen foundon a variety of devices. The haptic sensations output on the touchcontrol enhance interactions and manipulations in a displayed graphicalenvironment or when controlling an electronic device.

More specifically, the present invention relates to a haptic feedbacktouch control for inputting signals to a computer and for outputtingforces to a user of the touch control. The control includes a touchinput device including an approximately planar touch surface operativeto input a position signal to a processor of said computer based on alocation of user contact on the touch surface. One or more actuators arecoupled to the touch input device which can output a force to laterallymove the touch input device approximately parallel to its surface toprovide a haptic sensation to the user contacting it. The computer canposition a cursor in a graphical environment displayed on a displaydevice based on the position signal. The touch input device can be aseparate touchpad or included as a touch screen. The user can contactthe touch surface with a finger or other object, such as a stylus. Twoactuators can move the touch input device in orthogonal directionsparallel to the touch surface.

In another embodiment, a haptic feedback touch control for inputtingsignals to a computer and for outputting forces to a user includes atouch input device including an approximately planar touch surface whichinputs a position signal to a computer processor, a surface memberlocated adjacent to the touch input device, where the user can contactthe surface when pressing the touch input device, and an actuatorcoupled to the surface member. The actuator outputs a force on thesurface member to provide a haptic sensation to the user. The surfacemember can be translated laterally, approximately in a plane parallel tothe surface of the touch input device; for example, the surface membercan be positioned over the touch input device and approximatelycoextensive with the surface of the touch input device. Or, the surfacemember can be positioned to a side of the touch input device such thatthe user touches the touch input device with one finger and touches thesurface member with a different finger or palm for example, the surfacemember can be,positioned over a physical button that is located adjacentto said touch input device. Contact or inertial forces can be output onthe surface member.

In another aspect of the present invention, an actuator providing alinear force output includes a ferromagnetic piece including a centerpole located between two side poles, a coil wrapped around the centerpole, a magnet adjacent to the center pole and side poles, and a backingplate coupled to the magnet, where the backing plate and magnet movewith respect to the ferromagnetic piece when current is flowed in thecoil. Rollers can be positioned between the ferromagnetic piece andbacking plate to allow the motion. A flexure can reduce the relativemotion between plate and ferromagnetic piece in undesired directions andprovide a spring centering force.

In another aspect, a haptic touch device includes a piezoelectrictransducer coupled to a ground and including a metal diaphragm coupledto a ceramic element and a planar sensing element, such as a touchpad. Aspacer is provided between the piezoelectric transducer and the planarsensing element, the metal diaphragm contacting the spacer. A springelement provides a spring restoring force to the planar sensing element.

In another aspect of the present invention a method for providing hapticfeedback to a touch input device includes receiving a position signalfrom the touch input device indicating a contact location on a surfacewhere said user is pressing, and determining in which of a plurality ofregions on the surface the contact location is positioned. Forceinformation is provided to cause an actuator to output a force to theuser, the force associated with the user moving an object on or over thesurface of the touch input device. A function can be associated with theregion in which the contact location is positioned, such as rate controlfunction of a value or moving a displayed cursor. The can be output whenthe user moves the object over a boundary to the contacted region from adifferent region of the touch input device.

The present invention advantageously provides haptic feedback to aplanar touch control device of a computer, such as a touchpad or touchscreen. The haptic feedback can assist and inform the user ofinteractions and events within a graphical user interface or otherenvironment and ease cursor targeting tasks. Furthermore, the inventionallows portable computer devices having such touch controls to takeadvantage of existing haptic feedback enabled software. The haptic touchdevices disclosed herein are also inexpensive, compact and consume lowpower, allowing them to be easily incorporated into a wide variety ofportable and desktop computers and electronic devices.

These and other advantages of the present invention will become apparentto those skilled in the art upon a reading of the followingspecification of the invention and a study of the several figures of thedrawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a laptop computer device including ahaptic touchpad of the present invention;

FIG. 2 is a perspective view of a remote control device including atouchpad of the present invention;

FIG. 3 is a top plan view of a haptic touchscreen embodiment of thepresent invention;

FIG. 4 is a block diagram of a haptic system suitable for use in thepresent invention;

FIG. 5 is a perspective view of one embodiment of an actuator assemblysuitable for use in an inertial embodiment of the present invention;

FIG. 6 is a perspective view of the actuator assembly of FIG. 5 coupledto a touchpad;

FIG. 7 is a perspective view of a separate palm surface providinginertial tactile sensations adjacent to a touchpad;

FIG. 8 a is a perspective view of a piezoelectric transducer suitablefor use in providing inertial sensations in the present invention;

FIG. 8 b is a side elevational view of a piezoelectric transducer andstructure of the present invention suitable for providing hapticsensations with a touch device;

FIG. 9 is a perspective view of one embodiment of a translating surfacemember driven by linear actuators;

FIG. 10 is a top plan view of another embodiment of a translatingsurface member driven by a rotary actuator;

FIG. 11 is a perspective view of another embodiment of a translatingsurface member driven by a voice coil actuator;

FIG. 12 is a perspective view of an embodiment of a translating surfaceadjacent to a touchpad;

FIG. 13 is a perspective view of an embodiment of a touchpad translatedin one direction by a rotary actuator;

FIG. 14 is a perspective view of an embodiment of a touchpad translatedin two directions by rotary actuators;

FIGS. 15 a and 15 b are perspective views of a first embodiment of aflat E-core actuator of the present invention suitable for translating atouchpad or a separate surface;

FIG. 15 c is a side view of the actuator of FIGS. 15 a-15 b;

FIG. 15 d is a perspective view of the actuator of FIGS. 15 a-15 bcoupled to a touchpad;

FIGS. 16 a and 16 b are top and bottom perspective views of anotherembodiment of a flat E-core actuator of the present invention;

FIGS. 17 a-17 b are perspective and top views of surface-mounted E-coreactuators, of the present invention;

FIGS. 17 c-17 g are perspective and side views of the E-core actuatorsof FIGS. 17 a-17 b; and

FIG. 18 is a top plan view of an example of a haptic touchpad of thepresent invention having different control regions.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is a perspective view of a portable computer 10 including ahaptic touchpad of the present invention. Computer 10 can be a portableor “laptop” computer that can be carried or otherwise transported by theuser and may be powered by batteries or other portable energy source inaddition to other more stationary power sources. Computer 10 preferablyruns one or more host application programs with which a user isinteracting via peripherals.

Computer 10 may include the various input and output devices as shown,including a display device 12 for outputting graphical images to theuser, a keyboard 14 for providing character or toggle input from theuser to the computer, and a touchpad 16 of the present invention.Display device 12 can be any of a variety of types of display devices;flat-panel displays are most common on portable computers. Displaydevice 12 can display a graphical environment 18 based on applicationprograms and/or operating systems that are running on the CPU ofcomputer 10, such as a graphical user interface (GUI), that can includea cursor 20 that can be moved by user input, as well as windows 22,icons 24, and other graphical objects well known in GUI environments.Other graphical environments or images may also be displayed, e.g. agame, movie or other presentation, spreadsheet or other applicationprogram, etc.

Other devices may also be incorporated or coupled to the computer 10,such as storage devices (hard disk drive, DVD-ROM drive, etc.), networkserver or clients, game controllers, etc. In alternate embodiments, thecomputer 10 can take a wide variety of forms, including computingdevices that rest on a tabletop or other surface, stand-up arcade gamemachines, other portable devices or devices worn on the person, handledor used with a single hand of the user, etc. For example, host computer10 can be a video game console, personal computer, workstation, atelevision “set top box” or a “network computer”, or other computing orelectronic device.

Touchpad device 16 of the present invention preferably appearsexternally to be similar to the touchpads of the prior art. In manyembodiments disclosed herein, such a pad 16 includes a planar,rectangular smooth surface that can be positioned below the keyboard 14on the housing of the computer 10, as shown, or may be positioned atother areas of the housing. When the user operates the computer 10, theuser may conveniently place a fingertip or other object on the touchpad16 and move the fingertip to correspondingly move cursor 20 in thegraphical environment 18.

In operation, the touchpad 16 inputs coordinate data to the mainmicroprocessor(s) of the computer 10 based on the sensed location of anobject on (or near) the touchpad. As with many touchpads of the priorart, touchpad 16 can be capacitive, resistive, or use a different typeof sensing. Some existing touchpad embodiments are disclosed, forexample, in U.S. Pat. Nos. 5,521,336 and 5,943,044. Capacitive touchpadstypically sense the location of an object on or near the surface of thetouchpad based on capacitive coupling between capacitors in the touchpadand the object. Resistive touchpads are typically pressure-sensitive,detecting the pressure of a finger, stylus, or other object against thepad, where the pressure causes conductive layers, traces, switches, etc.in the pad to electrically connect. Some resistive or other types oftouchpads can detect the amount of pressure applied by the user and canuse the degree of pressure for proportional or variable input to thecomputer 10. Resistive touchpads typically are at least partiallydeformable, so that when a pressure is applied to a particular location,the conductors at that location are brought into electrical contact.Such deformability can be useful, in the present invention since it canpotentially amplify the magnitude of output forces such as pulses orvibrations on the touchpad as used in the present invention. Forces canbe amplified if a tuned compliant suspension is provided between anactuator and the object that is moved, as described in provisionalapplication No. 60/157,206, incorporated herein by reference. Capacitivetouchpads and other types of touchpads that do not require significantcontact pressure may be better suited for the present invention in, someembodiments, since excessive pressure on the touchpad may in some casesinterfere with the motion of the touchpad for haptic feedback. Othertypes of sensing technologies can also be used in the touchpad. Herein,the term “touchpad” preferably includes the surface of the touchpad 16as well as any sensing apparatus included in the touchpad unit.

Touchpad 16 can operate similarly to existing touchpads, where the speedof the fingertip on the touchpad correlates to the distance that thecursor is moved in the graphical environment. For example, if the usermoves his or her finger quickly across the pad, the cursor is moved agreater distance than if the user moves the fingertip more slowly. Ifthe user's finger reaches the edge of the touchpad before the cursorreaches a desired destination in that direction, then the user cansimply move his or her finger off the touchpad, reposition the fingeraway from the edge, and continue moving the cursor. This is an“indexing” function similar to lifting a mouse off a surface to changethe offset between mouse position and cursor. Furthermore, manytouchpads can be provided with particular regions that are each assignedto particular functions that can be unrelated to cursor positioning.Such an embodiment is described in greater detail below with respect toFIG. 18. In some embodiments the touchpad 16 may also allow a user to“tap” the touchpad (rapidly touch and remove the object from the pad) ina particular location to provide a command. For example, the user cantap or “double tap” the pad with a finger while the controlled cursor isover an icon to select that icon.

In the present invention, the touchpad 16 is provided with the abilityto output haptic feedback such as tactile sensations to the user who isphysically contacting the touchpad 16. Various embodiments detailing thestructure of the haptic feedback touchpad are described in greaterdetail below. Some embodiments may move a device housing or separatemoving surface, not the touchpad itself.

Using one or more actuators coupled to the touchpad 16 or an associatedsurface, a variety of haptic sensations can be output to the user who iscontacting the touchpad (or housing or separate surface). For example,jolts, vibrations (varying or constant amplitude), and textures can beoutput. Forces output to the user can be at least in part based on thelocation of the finger on the pad or the state of a controlled object inthe graphical environment of the host computer 10, and/or independent offinger position or object state. Such forces output to the user areconsidered “computer-controlled” since a microprocessor or otherelectronic controller is controlling the magnitude and/or direction ofthe force output of the actuator(s) using electronic signals.

In other embodiments, the touchpad 16 can be provided in a separatehousing that is connected to a port of the computer 10 via a cable orvia wireless transmission and which receives force information from andsends position information to the computer 10. For example, UniversalSerial Bus (USB), Firewire, or a standard serial bus can connect such atouchpad to the computer 10.

One or more buttons 26 can also be provided on the housing of thecomputer 10 to be used in conjunction with the touchpad 16. The user'shands have easy access to the buttons, each of which may be pressed bythe user to provide a distinct input signal to the host computer 12.Typically, each button 26 corresponds to a similar button found on amouse input device, so that a left button can be used to select agraphical object (click or double click), a right button can bring up acontext menu, etc. In some embodiments, one or more of the buttons 26can be provided with tactile feedback as described in U.S. Pat. No.6,184,868 and application Ser. No. 09/467,309, and both incorporatedherein by reference in their entirety. Other features of thesedisclosures may also be used with the present invention.

Furthermore, in some embodiments, one or more moveable portions 28 ofthe housing of the computer device 10 can be included which is contactedby the user when the user operates the touchpad 16 and which can providehaptic feedback. Having a moveable portion of a housing for hapticfeedback is described in U.S. Pat. Nos. 6,184,868 and 6,088,019, bothincorporated herein by reference. In some embodiments, both the housingcan provide haptic feedback (e.g., through the use of an eccentricrotating mass on a motor coupled to the housing) and the touchpad 16 canprovide separate haptic feedback. This can allow the host to control twodifferent tactile sensations simultaneously to the user; for example, avibration of a low frequency can be conveyed through the housing to theuser and a higher frequency vibration can be conveyed to the userthrough the touchpad 16. Each other button or other control providedwith haptic feedback can also provide tactile feedback independentlyfrom the other controls.

The host, application program(s) and/or operating system preferablydisplays graphical images of the environment on display device 12. Thesoftware and environment running on the host computer 12 may be of awide variety. For example, the host application program can be a wordprocessor, spreadsheet, movie, video or computer game, drawing program,operating system, graphical user interface, simulation, Web page orbrowser that implements HTML or VRML instructions, scientific analysisprogram, virtual reality training program or application, or otherapplication program that utilizes input from the touchpad 16 and outputsforce feedback commands to the touchpad 16. For example, many games andother application programs include force feedback functionality and maycommunicate with the touchpad 16 using a standard protocol/drivers suchas I-Force®, FEELit®, or Touchsense™ available from ImmersionCorporation of San Jose, Calif.

The touchpad 16 can include circuitry necessary to report controlsignals to the microprocessor of the host computer 10 and to processcommand signals from the host's microprocessor. For example, appropriatesensors (and related circuitry) are used to report the position of theuser's finger on the touchpad 16. The touchpad device also includescircuitry that receives signals from the host and outputs tactilesensations in accordance with the host signals using one or moreactuators. Some touchpads may be integrated with a printed circuit board(PCB) that includes some of these components and circuitry. In someembodiments, a separate, local microprocessor can be provided for thetouchpad 16 to both report touchpad sensor data to the host and/or tocarry out force commands received from the host, such commandsincluding, for example, the type of haptic sensation and parametersdescribing the commanded haptic sensation. Alternatively, the touchpadmicroprocessor can simply pass streamed data from the main processor tothe actuators. The term “force information” can include bothcommands/parameters and/or streamed data. The touchpad microprocessorcan implement haptic sensations independently after receiving a hostcommand by controlling the touchpad actuators; or, the host processorcan maintain a greater degree of control over the haptic sensations bycontrolling the actuators more directly. In other embodiments, logiccircuitry such as state machines provided for the touchpad 16 can handlehaptic sensations as directed by the host main processor. Architecturesand control methods that can be used for reading sensor signals andproviding haptic feedback, for a device are described in greater detailin U.S. Pat. No. 5,734,373 and copending application Ser. Nos.09/669,029, 09/565,207, 09/376,649, and 09/687,744, all incorporatedherein by reference in their entirety.

In existing touchpad, embodiments, such as those manufactured bySynaptics Corp., particular characteristics and features are provided.The standard surface material for a touchpad is textured Mylar, andtypically any non-conductive object can be used on the touchpad surfaceand be detected, though textured surfaces are better when a user'sfinger is used to point. The touchpad can also sense through thinoverlays. There is typically space available for the additional ofhaptic feedback components; for example, on a 40×60 touchpad, over halfof the board can be available for haptic circuitry.

Many touchpads include a “palm check” feature, which allows the laptopto sense whether the user is contacting the touchpad with a finger orwith a palm or other part of the hand. Since the user may only beresting his or her palm and not be intending to provide input, the palmcheck feature would ignore input that is determined to be provided by auser's palm. Basically, the palm check feature computes the contact areamade by the conductive object (finger, palm, arm, etc.). If the contactarea exceeds a certain threshold, the contact is rejected. This featurecan be turned off in many embodiments.

FIG. 2 is a perspective view of another embodiment of a device 30 whichcan include the active touchpad 16 of the present invention. The devicecan be a handheld remote control device 30, which the user grasps in onehand and manipulates controls to access the functions of an electronicdevice or appliance remotely by a user (such as a television, videocassette recorder or DVD player, audio/video receiver, Internet ornetwork computer connected to a television, etc.). For example, severalbuttons 32 can be included on the remote control device 30 to manipulatefunctions of the controlled apparatus. A touchpad 16 can also beprovided to allow the user to provide more sophisticated directionalinput. For example, a controlled apparatus may have a selection screenin which a cursor may be moved, and the touchpad 16 can be manipulatedto control the cursor in two dimensions. The touchpad 16 includes theability to output haptic sensations to the user as described herein,based on a controlled value or event. For example, a volume levelpassing a mid-point or reaching a maximum level can cause a pulse to beoutput to the touchpad and to the user.

In one application, the controlled apparatus can be a computer systemsuch as Web-TV from Microsoft Corp. or other computing device whichdisplays a graphical user interface and/or web pages accessed over anetwork such as the Internet. The user can control the direction of thecursor by moving a finger (or other object) on the touchpad 16. Thecursor can be used to select and/or manipulate icons, windows, menuitems, graphical buttons, slider bars, scroll bars, or other graphicalobjects in a graphical user interface or desktop interface. The cursorcan also be used to select and/or manipulate graphical objects on a webpage, such as links, images, buttons, etc. Other force sensationsassociated with graphical objects are described below with reference toFIG. 18.

FIG. 3 is a top plan view of another computer device embodiment 50 thatcan include any of the embodiments of haptic devices of the presentinvention. Device 50 is in the form of a portable computer device suchas “personal digital assistant” (PDA), a “pen-based” computer, “webpad,” “electronic book”, or similar device (collectively known as a“personal digital assistant” (PDA) herein). Those devices which allow auser to input information by touching a display screen or readout insome fashion are relevant to the present invention, as well as devicesallowing button input. Such devices can include the Palm Pilot from 3ComCorp. or similar products, pocket-sized computer devices from Casio,Hewlett-Packard, or other manufacturers, E-books, cellular phones orpagers having touch screens, laptop computers With touch screens, etc.

In one embodiment of a device 50, a display screen 52 positionedadjacent a housing 54 may cover a large portion of the surface of thecomputer device 50. Screen 52 is preferably a flat-panel display as iswell known to those skilled in the art and can display text, images,animations, etc.; in some embodiments screen 52 is as functional as anypersonal computer screen. Display screen 52 can be a “touch screen” thatincludes sensors which allow the user to input information to thecomputer device 50 by physically contacting the screen 50 (i.e. it isanother form of planar “touch device” similar to the touchpad 16 of FIG.1). For example, a transparent sensor film can be overlaid on the screen50, where the film can detect pressure from an object contacting thefilm. The sensor devices for implementing touch screens are well knownto those skilled in the art.

The user can select graphically-displayed buttons or other graphicalobjects by pressing a finger or a stylus to the screen 52 at the exactlocation where the graphical object is displayed. Furthermore, someembodiments allow the user to “draw” or “write” on the screen bydisplaying graphical “ink” images 56 at locations where the user haspressed a tip of a stylus, such as stylus 57, or a finger or otherobject. Handwritten characters can be recognized by software running onthe device microprocessor as commands, data, or other input. In otherembodiments, the user can provide input additionally or alternativelythrough voice recognition, where a microphone on the device inputs theuser's voice which is translated to appropriate commands or data bysoftware running on the device. Physical buttons 58 can also be includedin the housing of the device 50 to provide particular commands to thedevice 50 when the buttons are pressed. Many PDA's are characterized bythe lack of a standard keyboard for character input from the user;rather, an alternative input mode is used, such as using a stylus todraw characters on the screen, voice recognition, etc. However, somePDA's also include a fully-functional keyboard as well as a touchscreen, where the keyboard is typically much smaller than astandard-sized keyboard. In yet other embodiments, standard-size laptopcomputers with standard keyboards may include flat-panel touch-inputdisplay screens, and such screens (similar to screen 12 of FIG. 1) canbe provided with haptic feedback according to the present invention.

In some embodiments of the present invention, the touch screen 52 mayprovide haptic feedback to the user similarly to the touchpad 16described in previous embodiments. One or more actuators can be coupledto the touchscreen, or movable surfaces near the touchscreen, in amanner similar to the embodiments described below. The user canexperience the haptic feedback through a finger or a held object such asa stylus 57 that is contacting the screen 52.

The touch screen 52 can be coupled to the housing 54 of the device 50 byone or more spring or compliant elements, such as helical springs, leafsprings, flexures, or compliant material (foam, rubber, etc.), to allowmotion of the screen approximately along the z-axis, thereby providinghaptic feedback. The screen can also be provided with flexures or othercouplings allowing side-to-side (x and/or y) motion, similar to theappropriate embodiments described below.

FIG. 4 is a block diagram illustrating a haptic feedback system suitablefor use with any of the described embodiments of the present invention.The haptic feedback system includes a host computer system 14 andinterface device 12.

Host computer system 14 preferably includes a host microprocessor 100, aclock 102, a display screen 26, and an audio output device 104. The hostcomputer also includes other well known components, such as randomaccess memory (RAM), read-only memory (ROM), and input/output (I/O)electronics (not shown).

As described above, host computer 14 can be a personal computer such asa laptop computer, and may operate under any well-known operatingsystem. Alternatively, host computer system 14 can be one of a varietyof home video game console systems commonly connected to a televisionset or other display, such as systems available from Nintendo, Sega,Sony, or Microsoft. In other embodiments, host computer system 14 can bean appliance, “set top box” or other electronic device to which the usercan provide input. Computer 14 can also be a portable, hand-heldcomputer such as a PDA, or can be a vehicle computer, stand-up arcadegame, workstation, etc.

Host computer 14 preferably implements a host application program withwhich a user is interacting via interface device 12 which includeshaptic feedback functionality. For example, the host application programcan be a video game, word processor or spreadsheet, Web page or browserthat implements HTML or VRML instructions, scientific analysis program,movie player, virtual reality training program or application, or otherapplication program that may utilize input of mouse 12 and which outputshaptic feedback commands to the device 12. Herein, for simplicity,operating systems such as Windows™, MS-DOS, MacOS, Unix, Palm OS, etc.are also referred to as “application programs.” Herein, computer 14 maybe referred as providing a “graphical environment,” which can be agraphical user interface, game, simulation, or other visual environmentand can include graphical objects such as icons, windows, game objects,etc. Suitable software drivers which interface such software withcomputer input/output (I/O) devices are available from ImmersionCorporation of San Jose, Calif.

Display device 26 can be included in host computer 14 and can be astandard display screen (LCD, CRT, plasma, flat panel, etc.), 3-Dgoggles, or any other visual output device. Audio output device 104,such as speakers, is preferably coupled to host microprocessor 100 toprovide sound output to user. Other types of peripherals can also becoupled to host processor 100, such as storage devices (hard disk drive,CD ROM drive, floppy disk drive, etc.) other input and output devices.

Interface device 12 is coupled to the computer 14 by a bus 20, whichcommunicates signals between device 12 and computer 14 and may also, insome embodiments, provide power to the device 12. In other embodiments,signals can be sent between device 12 and computer 14 by wirelesstransmission/reception. In some embodiments, the power for the actuatorcan be supplemented or solely supplied by a power storage deviceprovided on the device, such as a capacitor or one or more batteries.The bus 20 is preferably bidirectional to send signals in eitherdirection between host 14 and device 12. Bus 20 can be a serialinterface bus, such as an RS232 serial interface, RS-422, UniversalSerial Bus (USB), MIDI, or other protocols well known to those skilledin the art; or a parallel bus or wireless link.

Device 12 may be a separate device from host 14 with its own housing, ormay be integrated with the host computer housing, as in the laptopcomputer of FIG. 1. Device 12 can include or be associated with adedicated local microprocessor 110. Processor 110 is considered local todevice 12, where “local” herein refers to processor 110 being a separatemicroprocessor from any host processors in host computer system 14.“Local” also may refer to processor 110 being dedicated to hapticfeedback and sensor I/O of device, 12. Microprocessor 110 can beprovided with software instructions (e.g., firmware) to wait forcommands or requests from computer host 14, decode the command orrequest, and handle/control input and output signals according to thecommand or request. In addition, processor 110 can operate independentlyof host computer 14 by reading sensor signals and calculatingappropriate forces from those sensor signals, time signals, and storedor relayed instructions selected in accordance with a host command.Suitable microprocessors for use as local microprocessor 110 includelower-end microprocessors as well as more sophisticated force feedbackprocessors such as the Immersion Touchsense Processor. Microprocessor110 can include one microprocessor chip, multiple processors and/orco-processor chips, and/or digital signal processor (DSP) capability.

Microprocessor 110 can receive signals from sensor 112 and providesignals to actuator 18 in accordance with instructions provided by hostcomputer 14 over bus 20. For example, in a local control embodiment,host computer 14 provides high level supervisory commands tomicroprocessor 110 over bus 20 (such as a command identifier and one ormore parameters characterizing the tactile sensation), andmicroprocessor 110 decodes the commands and manages low level forcecontrol loops to sensors and the actuator in accordance with the highlevel commands and independently of the host computer 14. This operationis described in greater detail in U.S. Pat. Nos. 5,739,811 and5,734,373, both incorporated herein by reference in their entirety. Inthe host control loop, force commands are output from the host computerto microprocessor 110 and instruct the microprocessor to output a forceor force sensation having specified characteristics. The localmicroprocessor 110 reports data to the host computer, such as locativedata that describes the position of the device in one or more provideddegrees of freedom. The data can also describe the states of buttons,switches, etc. The host computer uses the locative data to updateexecuted programs. In the local control loop, actuator signals areprovided from the microprocessor 110 to an actuator 18 and sensorsignals are provided from the sensor 112 and other input devices 118 tothe microprocessor 110. Herein, the term “tactile sensation” refers toeither a single force or a sequence of forces output by the actuator 18which provide a sensation to the user. For example, vibrations, a singlejolt, or a texture sensation are all considered tactile sensations. Themicroprocessor 110 can process inputted sensor signals to determineappropriate output actuator signals by following stored instructions.The microprocessor may use sensor signals in the local determination offorces to be output on the user object, as well as reporting locativedata derived from the sensor signals to the host computer.

In yet other embodiments, other hardware instead of microprocessor 110can be provided locally to device 12 to provide functionality similar tomicroprocessor 110. For example, a hardware state machine incorporatingfixed logic can be used to provide signals to the actuator 18 andreceive sensor signals from sensors 112, and to output tactile signals.

In a different, host-controlled embodiment, host computer 14 can providelow-level force commands over bus 20, which are directly transmitted tothe actuator 18 via microprocessor 110 or other circuitry if there is nomicroprocessor 110. Host computer 14 thus directly controls andprocesses all signals to and from the device 12, e.g. the host computerdirectly controls the forces output by actuator 18 and directly receivessensor signals from sensor 112 and input devices 118. Other embodimentsmay employ a “hybrid” organization where some types of forces (e.g.closed loop effects) are controlled purely by the local microprocessor,while other types of effects (e.g., open loop effects) may be controlledby the host.

Local memory 122, such as RAM and/or ROM, is preferably coupled tomicroprocessor 110 in device 12 to store instructions for microprocessor110 and store temporary and other data. In addition, a local clock 124can be coupled to the microprocessor 110 to provide timing data.

Sensors 112 sense the position or motion (e.g. an object on a touchpad)in desired degrees of freedom and provides signals to microprocessor 110(or host 14) including information representative of the position ormotion. Sensors suitable for detecting motion include capacitive orresistive sensors in a touchpad, contact sensors in a touchscreen, etc.Other types of sensors can also be used. Optional sensor interface 114can be used to convert sensor signals to signals that can be interpretedby the microprocessor 110 and/or host computer system 14.

Actuator(s) 18 transmits forces to the housing, manipulandum, buttons,or other portion of the device 12 in response to signals received frommicroprocessor 110 and/or host computer 14. Device 12 preferablyincludes one or more actuators which are operative to produce forces onthe device 12 (or a component thereof) and haptic sensations to theuser. The actuator(s) are “computer-controlled”; e.g., the force outputfrom the actuators is ultimately controlled by signals originating froma controller such as a microprocessor, ASIC, etc. Many types ofactuators can be used, including rotary DC motors, voice coil actuators,moving magnet actuators, E core actuators, pneumatic/hydraulicactuators, solenoids, speaker voice coils, piezoelectric actuators,passive actuators (brakes), etc. Some preferred actuator types aredescribed below. Actuator interface 116 can be optionally connectedbetween actuator 18 and microprocessor 110 to convert signals frommicroprocessor 110 into signals appropriate to drive actuator 18.Interface 116 can include power amplifiers, switches, digital to analogcontrollers (DACs), analog to digital controllers (ADCs), and othercomponents, as is well known to those skilled in the art.

In some of the implementations herein, the actuator has the ability toapply short duration force sensation on the housing or manipulandum ofthe device, or via moving an inertial mass. This short duration forcesensation can be described as a “pulse.” The “pulse” can be directedsubstantially along a particular direction in some embodiments. In someembodiments the magnitude of the “pulse” can be controlled; the sense ofthe “pulse” can be controlled, either positive or negative biased; a“periodic force sensation” can be applied and can have a magnitude and afrequency, e.g. the periodic sensation can be selectable among a sinewave, square wave, saw-toothed-up wave, saw-toothed-down, and trianglewave; an envelope can be applied to the period signal, allowing forvariation in magnitude over time. The wave forms can be “streamed” fromthe host to the device, as described in copending application Ser. No.09/687,744, incorporated herein by reference in its entirety, or can beconveyed through high level commands that include parameters such asmagnitude, frequency, and duration.

Other input devices 118 can be included in device 12 and send inputsignals to microprocessor 110 or to host 14 when manipulated by theuser. Such input devices include buttons, dials, switches, scrollwheels, knobs, or other controls or mechanisms. Power supply 120 canoptionally be included in device 12 coupled to actuator interface 116and/or actuator 18 to provide electrical power to the actuator.Alternatively, power can be drawn from a power supply separate fromdevice 12, or power can be received across bus 20. Also, received powercan be stored and regulated by device 12 (and/or host 14) and thus usedwhen needed to drive actuator 18 or used in a supplementary fashion.

The interface device 12 can be any of a variety of types; someembodiments are described further below. The touchpads or touchscreendescribed herein can be provided on a variety of types of devices, suchas gamepads, joysticks, steering wheels, touchpads, sphericalcontrollers, finger pads, knobs, track balls, remote control device,cell phone, personal digital assistant, etc.

Specific Embodiments

The present invention presents a variety of embodiments in which hapticfeedback is provided to a user of a laptop computer or other portablecomputing device, and/or to the user of any computing device having atouchpad or similar input device.

Some embodiments are based on displacing the skin of a user's fingerwhen it is in contact with a touchpad. These embodiments deliver highfidelity sensations while offering a good correlation between input andoutput right at the user's fingertip. Actuator and linkage solutions aredescribed to drive any of the translation embodiments. Other embodimentsare based on the stimulation of palm surfaces of the user that arenormally in contact with the laptop computer 10. These surfaces canprovide haptic sensations based on inertially coupled forces ortranslation of the palm surfaces. Translations of surfaces in plane withthe upper surface of the touchpad or laptop (i.e. in the X and/or Yaxes) are as effective at conveying haptic information as vibrations ordisplacements in the Z axis (those normal to the touchpad or laptopupper surface). This can be important when the volumetric constraints ofa laptop are considered.

In many of the embodiments described herein, it is also advantageousthat contact of the user is detected by a touch input device. Sincehaptic feedback need only be output when the user is contacting thetouch device, this detection allows haptic feedback to be stopped(actuators “turned off”) when no objects are contacting the touch inputdevice. This feature can conserve battery power for portable devices. Ifa local touch device microprocessor (or similar circuitry) is being usedin the computer, such a microprocessor can turn off actuator output whenno user contact is sensed, thus alleviating the host processor ofadditional computational burden until touch is again detected, when theactuator output is resumed.

In many preferred embodiments, haptics are added to a laptop computer orother device in a way that does not force the user to relearn how tocontrol the laptop or force the manufacturer to stretch design andmanufacturing too far from existing designs to provide the hapticcontent. For example, in laptop embodiments, as the user moves his orher finger across the touchpad, a cursor displayed on the laptop screenis correspondingly moved. Haptic effects can be output on the touchpador other laptop component contacted by the user when the cursorinteracts with a graphical object or area, when an event occurs, etc. Inother applications, haptic effects can be output when events orinteractions occur in a game or other application running on the laptop.

Other embodiments and descriptions of touchpads, devices, applications,and other component is suitable for use with the present invention aredescribed in copending patent application Ser. No. 09/487,737, filedJan. 19, 2000, which is incorporated herein by reference in itsentirety. Many types of actuators, sensors, linkages, amplificationtransmissions, etc. can be used with the present invention.

A touchpad surface, as manufactured currently, typically is coupled to aprinted circuit board (PCB) that includes necessary electronics andstandard connections for connecting and operating the touchpad in alaptop. Thus, when forces are applied to the touchpad, they are alsoapplied to the PCB that is often directly coupled to the touchpad, e.g.underneath the touchpad.

The embodiments herein are designed with particular guidelines andcharacteristics. For example, the particular haptic experiences thatfeel compelling in a certain embodiment, the location where the tactilecontent is focused or located physically, the spatial correlation of thehaptic feedback with the pointing of the user's finger on the touchpad,e.g. the feedback can be right under the finger, or originate somewherein the case/housing of the laptop, the required force strength and powerfor compelling feedback, the way the user interacts with the device andeffect on quality and content of the feedback (angle of finger contact,etc), and which actuators and mechanisms that can fit into the laptopform factor/housing are most desirable.

Preferably, existing haptic feedback software and drivers can be usedwith the embodiments described herein, such as TouchSense software fromImmersion Corp. A standardized module, such as a particular touchpad,that works for many different types of products is desirable, such asPDAs, laptops, cell phones, and remote controls.

The focus of these inventive embodiments is primarily on tactilefeedback implementations, not kinesthetic force feedback embodiments. Asdescribed herein, there are two basic classes of tactile feedback asapplied to the present invention: inertial haptic feedback and movingcontact haptic feedback. Inertial feedback is generated using inertiallycoupled vibrations and is based on moving an inertial mass that iscoupled to the housing/user through a compliant flexure, where the massmotions cause inertial vibrations in a surface contacted by the user.Moving contact feedback relates to directly moving a surface or member,with respect to an earth ground, against the user and usually isgenerated by creating small displacements of the user's skin.

The distinction between inertial and moving contact feedback can be madein terms of the actual mechanism used to provide information to theuser. Both inertial and tactile stimulation cause displacement of thehand or finger tissue; the inertial feedback is coupled through someenclosure by the transmissibility of that enclosure and the complianceof whatever holds the enclosure (e.g., a mouse pad plus the user's handfor an inertial feedback mouse). Moving contact feedback refers to amechanism that is more direct in how it stimulates the user's tissue.Examples would be tactile dots or surfaces that shear the skin of thefinger to cause sensation by locally deforming the finger or palmtissue. This distinction is made for the purposes of classifying twotypes of embodiments described below: inertial and surface translation.

A novel actuator, referred to as Flat-E herein, is described below andcan be used in all of the embodiments herein and represents a class ofvery low profile, power efficient, high performance, planar actuators. AFlat-E actuator can achieve acceptable performance levels and approachthe limited volume and form factor required for laptop and other deviceapplications.

Inertial Embodiments

These embodiments move an inertial mass to cause inertial hapticfeedback to the user, which is typically transmitted through anenclosure or mechanism such as a housing or other surface. In manycases, inertial mass does not impact any surfaces in its travel,although such impacts can alternatively be used to provide additionalhaptic effects.

FIG. 5 is a perspective view of one embodiment 150 of an actuatorassembly that can be used to provide inertial haptic sensations fortouchpads and housings of devices of the present invention. Embodimentsof an actuator assembly (or “inertial harmonic drive”) are described incopending application Ser. No. 09/585,741, incorporated herein byreference in its entirety. Actuator assembly 150 includes a groundedflexure 160 and an actuator 155. The flexure 160 can be a single,unitary piece made of a material such as polypropylene plastic (“livinghinge” material) or other flexible material. Flexure 160 can be groundedto the housing of the device 12, for example, at portion 161.

Actuator 155 is coupled to the flexure 160. The housing of the actuatoris coupled to a receptacle portion 162 of the flexure 160 which housesthe actuator 155 as shown. A rotating shaft 164 of the actuator iscoupled to the flexure 160 in a bore 165 of the flexure 160 and isrigidly coupled to a central rotating member 170. The rotating shaft 164of the actuator is rotated about an axis A which also rotates member 170about axis A. Rotating member 170 is coupled to a first portion 172 a ofan angled member 171 by a flex joint 174. The flex joint 174 preferablyis made very thin in the dimension it is to flex so that the flex joint174 will bend when the rotating portion 170 moves the first portion 172a approximately linearly. The first portion 172 a is coupled to thegrounded portion 180 of the flexure by a flex joint 178 and the firstportion 172 a is coupled to a second portion 172 b of the angled memberby flex joint 182. The second portion 172 b, in turn, is coupled at itsother end to the receptacle portion 162 of the flexure by a flex joint184.

The angled member 171 that includes first portion 172 a and secondportion 172 b moves linearly along the x-axis as shown by arrow 176. Inactuality, the portions 172 a and 172 b move only approximatelylinearly. When the flexure is in its origin position (rest position),the portions 172 a and 172 b are preferably angled as shown with respectto their lengthwise axes. This allows the rotating member 170 to push orpull the angled member 171 along either direction as shown by arrow 176.

The actuator 155 is operated in only a fraction of its rotational rangewhen driving the rotating member 170 in two directions, allowing highbandwidth operation and high frequencies of pulses or vibrations to beoutput. A flex joint 192 is provided in the flexure portion between thereceptacle portion 162 and the grounded portion 180. The flex joint 192allows the receptacle portion 162 (as well as the actuator 155, rotatingmember 170, and second portion 172 b) to move approximately linearly inthe z-axis in response to motion of the portions 172 a and 172 b. A flexjoint 190 is provided in the first portion 172 a of the angled member171 to allow the flexing about flex joint 192 in the z-direction to moreeasily occur.

By quickly changing the rotation direction of the actuator shaft 164,the actuator/receptacle can be made to oscillate along the z-axis andcreate a vibration on the housing with the actuator 155 acting as aninertial mass. Preferably, enough space is provided above and below theactuator to allow its range of motion without impacting any surfaces orportions of the housing. In addition, the flex joints included inflexure 160, such as flex joint 192, act as spring members to provide arestoring force toward the origin position (rest position) of theactuator 155 and receptacle portion 172. In some embodiments, the stopscan be included in the flexure 160 to limit the motion of the receptacleportion 122 and actuator 110.

Other embodiments can provide other types of actuator assemblies toprovide inertial sensations, such as a flexure that moves a separateinertial mass instead of the actuator itself. Or, an eccentric masscoupled to a rotating shaft of an actuator can be oscillated to providerotational inertial tactile sensations to the housing. The eccentricmass can be unidirectionally driven or bidirectionally driven. Othertypes of actuator assemblies may also be used, as disclosed in U.S. Pat.No. 6,184,868, such as a linear voice coil actuator, solenoid, movingmagnet actuator, etc.

In one embodiment, an actuator assembly such as described above may becoupled to any of various locations of a laptop housing or other devicehousing and used to vibrate parts of the housing, relying on thetransmission of vibrations through the product housing by the remotelymounted actuator module. The actuator assembly can; be attached todifferent areas of the laptop housing or components to provide inertialhaptic feedback when the inertial mass is oscillated.

The experience of the user may vary depending on the precise location ofthe actuator assembly on the laptop and with different tactile effectsthat are output. Locations for the coupling of the actuator assemblyinclude the housing bottom, side, or front, a surface engaged by theuser's palm when operating the device, an area adjacent to the touchpador touchscreen, or coupled to the touchpad or touchscreen. An effectivelocation may be the touchpad itself (e.g. coupling the actuator assemblyto the bottom of the touchpad). In some embodiments, if the touchpad isrectangular, more compliance may be achieved along the long axis of thetouchpad.

In general, haptic content is received by the user over a limitedfrequency range by attaching the actuator assembly to several locationson the laptop. Some locations or specific surfaces of the laptop orother device may act merely as sounding boards, turning mechanicalvibrations into more sound than tactile signal. Performance can dependon the compliance of the surface and actuator mounting. In someembodiments, higher force levels may be required to generate vibrationsfrom the housing that will propagate effectively to the touchpad ortouchscreen.

In many cases, the output of several types of haptic effects can befaint and muddy to the user, and effects having predominantly higherfrequencies may be more perceptible. One effective tactile effect forthis embodiment is a relatively high frequency “ringing” effect.Synpathetic vibrations in the laptop case and the touchpad may amplifythese vibrations. An actuator designed to resonate at a certain idealfrequency may be used to present a wide spectrum of frequencies byamplitude modulation techniques. For example, a compelling 25 Hz squarewave can be generated by modulating a 250 Hz natural frequency generatedby a tuned resonant actuator such as a large piezo ceramic resonator(see FIGS. 8 a-8 b). Such modulation schemes may rely on the actuatorbeing tuned to the environment it lives in and the object it must drive.Some type of vibration isolation system can be used in some embodimentsto keep the energy confined to the haptic module as opposed to allowingthe energy to dissipate off into sympathetic modes in other portions ofthe laptop computer or other device.

FIG. 6 is a perspective view of another embodiment, in which a touchpadmodule can be suspended in a compliant support structure and can becoupled to a harmonic source and vibrated along the Z-axis. In thisexample, the touchpad 200 can be moved with an actuator assembly 202that moves the touchpad surface in the Z-axis, perpendicular to thesurface of the touchpad. The touchpad can be coupled to the laptophousing 204 by one or more layers or supports of foam, rubber, or othercompliant material, where a strip 206 of foam provided around theperimeter of the touchpad between the touchpad 200 and the housing 204as shown in FIG. 6. The actuator assembly 202 can be coupled to thebottom of the touchpad assembly (or to another location) so that whenthe inertial mass is oscillated, the oscillations transfer to thetouchpad and allow it move in the Z-direction with respect to the laptophousing 204. For example, the actuator assembly can be bonded directlyto the bottom of the touchpad PCB. A floating assembly of a touchpad anda bezel (surface surrounding the touchpad) can alternatively be moved,as opposed to just moving the touchpad module in the Z-axis.

In another embodiment, a stand-alone touchpad device can be used, wherethe touchpad is housed in a separate housing and communicates with thelaptop or other device via wires or transmissions. In one embodiment,the stand-alone touchpad device can be attached to a palm pad (or othermember), with the actuator assembly coupled to the pad. When theinertial mass of the actuator assembly is oscillated, the inertialsensations are transmitted through the member to the touchpad, i.e. thiseffectively provides inertial coupling from the actuator assembly to thetouchpad surface. A foam layer (or other compliant layer) can be coupledbetween the pad and ground to provide compliance and allow the pad andtouchpad to move inertially. This embodiment may feel more compellingthan the embodiments in which the actuator assembly is mounted to thelaptop near or on the built-in touchpad, possibly due to the complianceof the foam which can allow stronger sensations to be output.

The entire touchpad can be provided with haptic sensations as a singleunitary member; or, in other embodiments, individually-moving portionsof the pad can each be provided with its own haptic feedback actuatorand related transmissions so that haptic sensations can be provided foronly a particular portion. For example, some embodiments may include atouchpad having different portions that may be flexed or otherwise movedwith respect to other portions of the touchpad.

In another embodiment, the surface around or adjacent to the touchpad iscoupled to harmonic vibration source (e.g., actuator assembly) andvibrates in one or more axes. For example, palm rest surfaces may bedriven by an inertial actuator assembly housed in the laptop. FIG. 7 isa perspective view of one example of an inertially-driven palm restsurface. A laptop computer 210 includes a touchpad 212 that functionslike a typical touchpad. A palm rest surface 214, is positioned adjacentto the touchpad 212, where the surface 214 can be attached to the laptophousing on a layer of resilient open cell foam or other compliantmaterial. In some embodiments, the surface 214 can be textured withdivots and/or bumps to allow a stronger contact by the user to thesurface. An actuator assembly 216 is coupled to the palm rest surface214; in the embodiment shown, the assembly 216 is coupled to theunderside of the surface 214. The assembly can be any of the actuatorassemblies described above. For example, the actuator assembly 216 canprovide z-axis oscillations to the palm rest surface 214.

The user preferably rests a palm and/or some fingers on the palm restsurface 214 while the user is using the touchpad 212 with a pointingfinger(s). Thus, the user is able to feel haptic sensations through thepalm rest surface while operating the touchpad. Alternatively, one handof the user is used to point and operate the touchpad, while the otherhand rests on the palm surface 214 and senses haptic feedback. The palmsurfaces are implemented as practically unavoidable contact surfaces andconsequently a user is not likely to miss very many haptic events whileusing the touchpad. In some embodiments, how hard the user rests thepalms on the surface can make a slight difference in perceived magnitudeover the useful bandwidth; and may be a result of stiffness and mass ofthe particular device used. The stiffness of the coupling of the palmsurface with the housing can be adjusted for a particular feel indifferent embodiments.

In a related embodiment, the actuator assembly can be mounted indifferent areas. For example, the actuator assembly can be attached tothe bottom of an extension of a palm rest surface made of texturedmaterial mounted on a layer of resilient open cell foam or othercompliant material.

In other embodiments, the palm surface can be translated in the X and/orY directions, similarly to the touchpad translation described below. Theinertial actuator assembly could be used to force the translation, or adifferent type of actuator, e.g. high actuator authority and fairly highstiffness in the translation mode to avoid unintentional hard stoplimiting distortion, etc. The translating palm surface can be suitablefor a flat actuator so that the assembly can be integrated into thelaptop housing; flat actuators are described below.

FIG. 8 a is a perspective view of an actuator that can be used inanother embodiment of an inertial haptic feedback device of the presentinvention. In this embodiment, a higher frequency mechanical oscillator,mechanically coupled to the touchpad, is modulated. One example of suchan implementation may include a large-diameter commercially availablethin piezoelectric transducer 230, e.g., 60 mm in diameter with naturalfrequencies of 300 to 400 Hz when supported peripherally. Thepiezoelectric transducer preferably includes a thin diaphragm (sheet) ofmetal 231. One embodiment may include an added mass 232 at the ceramiccenter of the piezo diaphragm in order to add inertial mass and lowerthe natural frequency to achieve stronger inertial tactile sensationsfrom the oscillating mass. The outer periphery of transducer 230 can begrounded and the mass 232 can oscillate normal to the disc surface tocreate inertial haptic sensations to the housing to which the transduceris attached.

Actuator 230 can function as a harmonic oscillator that runs at arelatively high frequency that transmits sensations to the hand or partof the laptop to which it is attached. Amplitude modulation (envelopecontrol) may be used to produce a wider haptic spectrum than the singlefundamental drum mode. Large diameter piezo drivers are available, forexample, from Kingstate of Taiwan. Differently sized discs can also beused.

To provide the desired haptic sensations, a large piezo buzzer shouldprovide large sustainable displacements (accelerations) of the mass andthe carrier frequency (the frequency at which it oscillates) should bemodulated with the haptic signal. Some electronics may be needed tooperate this type of actuator. A high voltage supply can be generatedfrom 5 volts. An oscillation circuit, e.g., self exciting, can drive theelement. There can be a gating feature to start and stop the oscillationas well as a proportional control to allow modulation of the amplitudeof the output. An all-digital implementation may be provided by gatingthe oscillator on and off.

FIG. 8 b is a side elevational view of another embodiment 234 of apiezoelectric transducer providing haptic feedback, where the transducerapplies (non-inertial) vibrations directly to the touchpad (ortouchscreen) along the z-axis (also see parent application Ser. No.09/487,737). A housing 236 of the laptop can include bezels whichoverlay a touchpad member 238, which the user physically contacts toprovide input to a computer. The touchpad member 238 can include therequired electronics to interface the touchpad with other electroniccomponents. The touchpad member 238 can rest on a spacer 240 having aparticular mass chosen to allow efficient haptic output. The spacer 240rests on the edge of a piezo metal diaphragm 231, which is part of thepiezo transducer, and where an electrical lead 241 is coupled betweenthe diaphragm 231 and a signal source 246. The piezo ceramic element242, also part of the piezo transducer, is coupled to the metaldiaphragm 231 and an electrical lead 243 is coupled between the element242 and the signal source 246. A conductive electrode is plated on theceramic element 242. A contact pad 248 is positioned between the element242 and a bottom housing 250, where the contact pad is rigidly coupledto both ceramic element 242 and housing 250. The contact pad 248 is madesmall so that the diaphragm 231 will have increased bending, resultingin greater acceleration and stronger haptic effects. The bottom housing250 can include a printed circuit board (PCB), for example. One or morepreloaded spring elements 252 couple the touchpad member 238 to thebottom housing 250, e.g. leaf springs, helical springs,.etc.

In operation, the piezo transducer moves along the z-axis when anoscillating current from signal source 246 is flowed through thediaphragm 231 and the ceramic element 242. Thus, spacer 240 is providedonly at the edges of the diaphragm 231 to allow the inner portion of thediaphragm and the ceramic element 242 to move, and the ceramic elementpushes against the bottom housing 250, causing the diaphragm 231 to pushagainst the spacer 240, which in turn pushes against the touchpadelement 238. This pushes the touchpad element up, and the springelements 252 provide a spring return force on the touchpad so that itwill return to its neutral position. When the piezo transducer similarlymoves in the opposite direction, as directed by the oscillating signal,this moves the touchpad element 238 down toward the bottom housing 250.The touchpad element thus oscillates along the z-axis and provideshaptic sensations to the user contacting the touchpad element.

In some embodiments, the components of the touchpad embodiment 234 canbe chosen to provide more effective haptic sensations. For example, ifthe piezo transducer oscillates at close to a natural frequency of themechanical system (including the transducer itself), then strongerforces and more effective haptic sensations can be output. The naturalfrequency of this moving mechanical system can be approximatelyexpressed as the square root of the expression k1 plus k2 divided by m,as shown below:fn≈{square root}(k 1+k 2 /m)where fn is the natural frequency, k1 is the spring constant of themetal diaphragm 231 of the piezo transducer, k2 is the spring constantof the spring elements 252, and m is the total mass of the spacer 240,the touchpad 238, and the parts of the suspension attached to thetouchpad. This mass, as well as the spring constants, can be selected toprovide a desirable low natural frequency, such as about 120 Hz or less,which tends to cause effective haptic sensations. The spacer 240 canallow multiple piezo transducers, e.g. positioned side by side, to bepositioned against the bottom housing 250, so that the multipletransducers can be driven in unison for stronger haptic effects or atdifferent times to provide sensations at particular locations of thetouchpad element 238.

One way to provide the drive signal is to provide an initial oscillatingcarrier signal at or near the natural frequency fn, modulate the carriersignal with an effect envelope, if applicable (e.g. shape the amplitudeto a desired configuration to provide a desired frequency or effect),and drive an amplifier with the modulated signal, which in turn drivesthe piezo transducer. A sine wave carrier signal, as opposed to squarewave or other types, used in such an embodiment tends to produce quieterhaptic effects in the described embodiment of FIG. 8 b, which is oftenmore desirable. Some ways of producing lower frequencies with a highfrequency oscillation are described in copending patent application Ser.No. 09/______, filed Jul. 17, 2001, entitled, “Providing Enhanced HapticFeedback Effects,” which is incorporated herein by reference in itsentirety.

In an alternate embodiment, the piezoelectric transducer and'spacer canbe reversed in orientation so that the spacer 240 contacts the bottomhousing 250, the diaphragm 231 rests on the spacer 240, the ceramicelement 242 is positioned above the diaphragm, and the ceramic elementdirectly impacts the touchpad element 238 or a pad coupled to thetouchpad member when it is oscillated by the driving signal. In yetother embodiments, the ceramic element can be directly coupled to thetouchpad element, but in general less strong and effective hapticeffects are the result.

Surface Translation Embodiments

These embodiments translate a surface that is in contact with the userto provide haptic feedback to the user. The user feels the translatingsurface in shear with his or her skin, creating an immediate sensation.This type of haptic feedback is based on either surface motion in-planewithout interactions with fixed surfaces or relative motion betweenadjacent surfaces that are in contact with the users finger or hand.Both translation of a surface in contact with or adjacent to thetouchpad module surface (FIGS. 9-12), as well as displacement of thetouchpad surface itself (FIGS. 13-14) are embodiments described below,as well as actuators that may be used for either application (FIGS.15-17). Moving-surface inventions described in U.S. Pat. No. 5,184,868can also be applied; this patent is incorporated herein by reference inits entirety.

Small (<1 mm) displacements between adjacent surfaces provide goodsignal transmission into finger tissue. Enhanced surfaces may have aphysical surface texture (bumps, roughness, etc.) and will be shaped toengage the user for any position or orientation. The advantage of thisapproach is that it is easy to feel the forces over a wide range ofphysical orientations and finger positions in many embodiments, smalllateral translations (displacements under the finger tip between 0.25 mmto 0.5 mm) are often more effective than remote inertial vibrations oreven out-of-plane (z-axis) vibrations right under the touchpad, e.g.,inertial coupling can have a more remote and disconnected feeling insome embodiments. Translating a surface above a touchpad or the touchpaditself typically requires less volume and consumes less power thanmoving the same touchpad surface in the Z axis, since a large mass isnot being accelerated for surface translation. Surface translationapproaches are often less sensitive to the orientation or manner inwhich the user's finger approaches the touchpad, as well.

Separate Surface Translation

Displacing a separate surface member positioned on top of a touchpadmodule is very effective at providing well-correlated feedback. Thefeedback feels sufficiently synchronized that clear surfaces may betranslated above visual displays, as in PDAs or touch screens.Translation of other surfaces to the side or otherwise adjacent to thetouchpad can also be performed in other embodiments.

FIG. 9 is a perspective view of a first separate surface translationembodiment 250 in which a separate thin surface that is in slidingcontact with the touchpad module is moved laterally under the finger. Atranslating surface member (“surface”) 252 is positioned on top of andcovering the fixed touchpad 254. Extension members 256 a and 256 b whichare coupled to the translating surface 252 can be extended approximatelyperpendicularly in the x- and y-directions away from the touchpad 254.An actuator 258 a and 258 b can be coupled to each associated extensionmember 256 a and 256 b, respectively. In the described embodiment, theactuators 258 are linear actuators outputting a linear force on theassociated extension member 256, thereby moving the translating surfacein the direction of the output force. For example, the actuators can be“E” core actuators similar to those described in application Ser. No.09/608,130. The two pole magnet 259 is not shown on the actuator 258 bto reveal the coil 260 under the ferromagnetic piece 382.

The sliding surface 252 can be any of a variety of stiff orsubstantially stiff materials; for example, Kapton (polyamid) flexibleprinted circuit board material can be used. The extension members 256can incorporate a stiffener section to prevent buckling. The slidingsurface 252 can be a textured surface that provides a friction force toengage the user skin tissue in contact with the surface. A region on thetop of the moving surface 252 can include the texture having sufficientsurface roughness to provide purchase on the skin without feeling roughto touch. On the underside of the moving surface, a low friction coatingcan be included to promote sliding between surface 252 and touchpad 254.This underside component can be very thin, for example, less than 0.010inches (0.25 mm) thick.

The user points to and contacts the moving surface 252 just as if itwere the touchpad 254 itself The surface 252 is made thin enough so thatthe touchpad 254 can detect all the contact of the user to the surface252 as if the user were touching the location of the touchpad directlyunderneath the location touched on the surface 252.

In some embodiments, the actuators can be located relatively far fromthe moving surface (e.g., >10 cm) and in these cases the stifferextension members 256 may need to transmit tension and compression withas little friction or out-of-plane movement as possible. Fiberlaminations of glass or carbon can perform this function, for example.

In some moving magnet actuator embodiments, thin rare earth magneticpieces can be laminated to the moving surface 252 to act as the movingmagnets. A high level of integration can be achieved, for example, ifthe moving magnet pieces are on the order of <1 mm in thickness and the“E” core and coil are located below the distal segments of theextensions 256, e.g., mounted directly to the touchpad PCB itself. Thecoil wires can be soldered directly to the touchpad PCB.

FIG.10 is a top plan view of another translating surface embodiment 270in which a separate moving tactile surface is positioned above, and insliding contact with, the touchpad. This surface is translated relativeto the touchpad by a high bandwidth actuator through a high fidelitymechanical linkage.

In this embodiment, a translating surface 272 is positioned over atouchpad 274, similar to the embodiment of FIG. 9. An extension member276 can protrude in a direction (x-direction here) towards a rotaryactuator 278, which is this example is grounded to the laptop housing280. The actuator 278 can be a DC rotary motor having a rotatable shaft282 that is coupled to a coupling linkage 284 that is in turn coupled tothe extension member 276. For example, a portion of the linkage from theactuator assembly 150 described above can be used. When the actuator 278rotates the shaft 282 in either direction, the linkage converts therotation to surface 272 translation in a corresponding direction (leftor right). For example, a displacement of about +/− 1 mm can beachieved. The user feels the surface translation when moving a fingerover the surface 272. Motor rotation can result in very clean highfidelity translation in the X axis. A DC motor design may work in alaptop given spare volume out at the sides or locations in the front ofthe enclosure or housing. A similar extension, linkage and motor can beprovided in the y-direction to move the surface 272 in that direction.The input of the user is detected on the touchpad through the movingtactile surface.

The thin surface can be trimmed to fit inside the touchpad area with asmall border all around. A rectangular extension can be cut out of alarger lamination to provide a fairly rigid strip that is driven with anactuator. This strip should be wide enough to allow the actuator to pushon it in operation without the strip buckling.

As in the embodiment of FIG. 9, a smooth surface can be provided on theunderside of surface 272 that contacts the touchpad to provide a smoothlow-friction sliding interface with the touchpad plastic covering thatthe user's finger normally touches. The top side of the moving surface272 can be made frictional to allow a good user grip, e.g. a texturelike fine sandpaper. This can provide an excellent contact surfacebecause it provides some mechanical bonding with the finger surface, butis not rough enough to feel rough to touch. Other embodiments can use avariety of types of friction surfaces. Other embodiments may also useflatter actuators, such as moving magnet actuators or voice coilactuators.

Two strips 286 of plastic or other material can be attached to the bezelsurrounding the touchpad (i.e: the rim of the housing opening for thetouchpad) and covering the edges of the surface 272 in order toconstrain the moving surface 272 and keep it flat against and parallelto the touchpad 274.

The embodiments of FIGS. 9 and 10 can provide compelling hapticsensations. Adding a surface above the touchpad does not substantiallyinterfere with the sensor operation of the touchpad. A user canconcurrently point and receive haptic feedback through motion of thissurface relative to the fixed touchpad. The perceived correlation of theimparted feedback with movement is good. It is simple for the user topoint and navigate a cursor or other object (i.e., provide input to thelaptop or other electronic device) when touching and moving a fingerover the translation surface above the touchpad. In some embodiments,the moving surface can be held above, not in close contact with, thetouchpad and so some compression by the user may be required to take thefree play out and come into proximity with the sensor array.

When moving a cursor over displayed scroll bars and around on thedesktop GUI displayed by the laptop, the user feels distinct, highfidelity effects that are well correlated spatially with the cursor. Thecharacter of the correlation may be different depending on whether theuser moves a finger or object in the x- or the y-axis. The actuator inthe shown embodiment 270 moves the surface 272 in the x-axis.Consequently, moving the cursor up and down over icons, the user mayfeel pops or similar tactile effects as unidirectional if the user doesnot concentrate on or observe that the motion of the surface 272 isperpendicular to the cursor motion.

Motion of the user's finger in the translated direction—the x-axis inthe example of FIG. 10—tends to be more compelling. For example, as theuser drags a finger in the x-direction to move a cursor from onedisplayed radio button to the next, the surface 272 may lead the userinto the next button and can feel like a detent even though very smallmotions of the surface are being generated. A surface translation forceopposing the direction of motion can be effective, e.g. if the user ismoving left onto an icon, a translation force directed to the rightfeels crisp and natural. If haptic feedback is allowed in only one axis,the y-axis may be a better choice in some embodiments because there maybe more vertically-oriented content on a GUI desktop and inapplications.

A short, distinct pulse can provide excellent transitions when movingthe cursor from one object to another, such as between graphicalbuttons. Vibrations can be conveyed to the user in surface translationembodiments by oscillating the actuator driving the surface, e.g. with asine or other periodic wave, and thereby oscillating the translatingsurface in opposite directions.

The user also may naturally tend to take his or her finger off of thetouchpad between motions that control the cursor, and an inherent springcentering of the motor and linkage can return the moving surface 252 or272 to a neutral (origin) position, ready for the next interaction. Thecontrolled cursor is not moved while the feedback apparatus has movedback to the neutral origin position, since only the surface above thetouchpad moves and does not provide input to the computer through thetouchpad like a user's finger. This subtlety is more readily provided inthis embodiment than if the touchpad surface itself were translated, asin other embodiments described herein.

Motion in a particular direction allows the surface translationembodiments to act in some embodiments as a relative pointing devicewith local pseudo-kinesthetic feedback. Tactile feedback is still theprimary type of haptic feedback provided in such an embodiment, but thesmall displacements of the surface can be dramatically perceived asdirected spring forces acting in such a way that they feel like detent“slopes” that force the user's finger in a direction, even though theyare just pops.

The overall stiffness of the actuator can affect results. If the userpresses too strongly on the moving surface, then the user may move thesurface while dragging/pointing the finger and this can run the actuatorout of its spring center. A preferred embodiment has a forceful butstiff actuator, one that the user can barely back-drive by pressingstrongly.

Having particular amount of travel or compliance on the moving surface,e.g. about 2 mm, is desirable in some embodiments. There is a strongspring centering from the motor and linkage, and moving the cursorbetween two objects, such as buttons in a GUI, can be very realisticbecause the user may perceive true kinesthetic force feedback untilfinger pressure is decreased and the finger is moved quickly across thescreen in a relative mode. The haptic effects which are output aresimple tactile pops, and no actual kinesthetic springs are providingforce in the X or Y directions. However, the user senses that his or herfinger is being pulled into an adjacent object, e.g. the next button.

It should be noted that kinesthetic force feedback is possible in adifferent embodiment. For example, if the user keeps his or her fingerin one place on the moving surface, and the moving surface has a largeenough displacement, forces can be output in the degrees of freedom ofmotion of the moving surface, providing kinesthetic force feedback. Thesensor of the touchpad can be used as the sensor indicating the positionof the finger/moving surface for computation of the force, such as aspring force having a magnitude dependent on the distance that is movedfrom an origin of the spring. Thus, such an embodiment would be a dualmode haptic system, including both tactile and kinesthetic modes.

Some embodiments of the moving surface may allow sliding by the user,while others may be very stiff with little sliding. In many embodiments,if the maximum permitted movement of the surface is enough to allowtraversal between two adjacent graphical targets, then the kinestheticmode can be effective and user may not notice that he or she is movingthe surface—it feels natural. Some embodiments can provide translationand forces in two axes (X and Y), allowing this kinesthetic directedfeedback (real springs) in all directions of the touchpad.

Haptic effects may not feel the same if the user is not moving his orher finger or object on the touchpad. There is often content and valuein the correspondence of touchpad motion with the haptic effect (e.g., adetent pop effect). For example, it is effective when the user finger ismoving and receiving the pop effect when the finger translates themoving surface to the transition point between the icons or buttons.

Many of the advantages described above for separate translating surfacesare also applicable to translating the touchpad surface, described indetail below.

FIG. 11 is a perspective view of another embodiment 290 of a separatetranslating surface and moving coil actuator. In this embodiment, aframe 292 is positioned over the touchpad 294 of the device. Frame 292includes a thin surface portion 296 which is located directly above thetouchpad 294 and is thin enough to allow. the user's contact on theportion 296 to be detected by the touchpad 294 underneath. Frame 292also includes an integrated voice coil 298 which is part of a voice coilactuator 300. The coil 298 can be wire traces that are molded into theframe 292, which can be a PCB. The other parts of the actuator 300include a stationary two-pole magnet 302 positioned over the coil 298and grounded to the laptop housing, and a backing plate 304 made ofsteel, positioned on the other side of frame 292 and grounded to thehousing, and used for a flux return path. The steel subassembly can beattached to the touchpad PCB itself, for example.

Thus, the magnetic fields of the magnet 302 and the current flowingthrough coil 298 interact to cause a linear force on the frame 298,which causes the frame and portion 296 to move as indicated by arrow306. This provides haptic sensations to the user similarly to theseparate translating surface embodiments described above. The housingcan surround the entire frame except for an opening surrounding theportion 296 of the frame 292. In some embodiments, wires from the coil298 can be connected to the touchpad PCB using a separate flex circuitfinger that branches off of the moving frame 292.

FIG. 12 is a perspective view of another embodiment 310 of a separatetranslating surface. In this embodiment, a surface surrounding thetouchpad is translated in x- and/or y-direction with respect to thetouchpad surface. Thumb surface 312 is positioned at the bottom side ofthe touchpad 314 and is rigidly coupled to a link member 295. Linkmember 316 is coupled to a flexible link 318, which is coupled to therotatable shaft of an actuator 320 that is grounded to the laptophousing. When the actuator 320 rotates the shaft, the flexible link 318moves the link member 316 linearly as indicated by arrow 322, whichmoves the thumb surface 312 linearly along the x-axis. The thumb surface312 is shown in sliding contact with a standard button (not shown) whichis directly underneath the surface 312.

The user can rest his or her thumb, palm, or finger on the thumb surface312 while operating the touchpad in order to feel the haptic sensations.To press the button located underneath the thumb surface 312, the usersimply presses down on the surface 312. Overall, the sensations tend tobe similar to the sensations for the other translating surfacesdescribed above. In other embodiments, the link member 316 can be muchlonger to allow desired placement of the actuator 320 in the housing ofthe laptop or other device.

One disadvantage is that there is no feedback to the user unless theuser has a thumb, finger, or palm on the thumb surface area. The usermay have to reach for other buttons to type and then lose the hapticexperience. A larger surface 312 or palm pad extension can be used inembodiments in which it may be difficult to keep the user's thumb on thesurface 312 while using the same hand to point with the touchpad.

Touchpad Translation

These embodiments translate the touchpad surface itself rather thanmoving a separate surface. The user feels the translating touchpadmoving laterally, in shear with his or her skin, creating an immediatesensation. The touchpad can be moved relative to a fixed surround, suchas a laptop housing.

FIG. 13 is a perspective view of one embodiment 330 providing atranslating touchpad surface. Touchpad 332 is moved relative to ahousing 334, such as a laptop or PDA housing, by an actuator 336. In thedescribed embodiment, the actuator 336 is a rotary actuator, such as aDC motor, having a rotating shaft 338 that is coupled to a linkage 340.The linkage 340 is coupled to a bracket 342 at its other end, where thebracket 342 is coupled to the underside of the touchpad 332 module. Thelinkage includes joints and/or flexibility/compliance to allow therotational motion of the shaft 338 to be converted to linear force onthe bracket 342, thereby causing the touchpad 332 to move laterally asshown by arrows 344. For example, the linkage can be made ofpolypropylene, similar to the linkages of the actuator assembly of FIG.5. The laptop housing can serve as a constraining structure for themoving touchpad module.

For example, a standard DC motor can be used for actuator 336 and apolypropylene linkage assembly for linkage 340. In one embodiment, thehaptic feedback components can reside where optional components for thelaptop are normally placed, such as an optional disc drive.

In other embodiments, the actuator 338 can be located remotely from thetouchpad 332, e.g., wherever space is available in the housing asopposed to directly underneath the touchpad as illustrated in FIG. 13.Linkages can be used to locate the actuator(s) remotely from thetouchpad, as shown in FIG. 14 below.

Translating the entire touchpad in one or two axes may be one goodoverall haptics approach. Very small displacements (0.2 mm<×<0.5 mm) ofthe touchpad are desired to provide useful haptics. The powerconsumption for this embodiment when evaluated within a practicalmagnitude range can be less than the consumption of currently availableinertial mice interface devices, which can receive all needed power overthe interface to the host computer, such as USB.

Some advantages are apparent in this type of embodiment. Feedbackexperience is direct, well correlated with pointing, and precise.Implementation can be flexible and unobtrusive, and addition of hapticcomponents does not alter how the touchpad is used. The translatingsurface has a small displacement requirement compared with inertialapproaches—this can lead to reduced power consumption and manufacturingbenefits. In some embodiments, the motion of the touchpad can beoriented at an angle in the x-y plane. Some disadvantages may includeuse of a DC motor, which are relatively large, a flexible linkage mayneed a lot of clearance and may cause friction, and power consumptionmay be relatively high.

FIG. 14 illustrates a perspective view of another embodiment 350 of amoving touchpad, in which the touchpad may be moved in both X and Ydirections. The touchpad 351 is directly coupled to a first linkagemember 351, which is coupled to a rotating shaft of an actuator 353 by aflexible member 354, such as polypropelene. Actuator 353 is grounded tothe laptop housing. When actuator 353 rotates its shaft, the flexiblemember 354 converts the rotary motion to linear motion and translatesthe linkage member 352 in the x-direction, which in turn translates thetouchpad as indicated by arrow 355. At the distal end of the firstlinkage member 354, a second linkage member 356 is coupled, e.g. by aflexible coupling.

A second actuator 358, grounded to the laptop housing, is coupled to theother end of the second linkage member 356 by a flexible member 357,where the axis of rotation of the rotating shaft of the actuator 358 issubstantially the same as the axis of rotation of the actuator 353. Therotary force output by the rotating shaft of the actuator 358 isconverted to a linear force by the flexible member 357. This linearforce causes the second linkage member 356 to move linearly along itslength, which in turn causes the first linkage member 352 to pivotapproximately about its end near actuator 353 along the y-axis and causethe touchpad 351 to move approximately along the y-axis. The actuators353 and 358 can be, for example, DC motors or any other type ofactuator, e.g. linear actuators can also be used, as described below inFIGS. 15-17. The linkage members can be made of any suitable material,e.g. carbon fiber. Preferably, very little energy is absorbed by thegrounded structure or by unwanted deformations in the linkage assembly.

Thus, the mechanism decouples the x- and y-motions; by activatingactuator 353, x-axis motion is provided, and by activating actuator 358,y-axis motion is provided; both x- and y-axis motion can be provided byactivating both motors simultaneously. Both actuators can be driveneither together (common mode) or differentially (differential mode) toachieve pure X or Y movement without binding the linkage parts.Furthermore, any combination of drive current will produce a resultantforce along any arbitrary axis with the same fidelity and lack ofbinding.

One embodiment may use firmware for rapid evaluation and output of X andY forces, e.g. software running on a local controller such as amicroprocessor, or running off the host CPU. In some embodiments, suchfirmware may be too complex, so that alternatively, a mechanism with anelectronic way of switching between the two principle feedback axes canbe used. In one embodiment, the two DC motors can be connected in aseries circuit with switch that reverses the current through one of thetwo motors.

In the embodiment of FIG. 14, the user may feel the difference betweenx- and y-directional forces when moving a finger or object on thetouchpad in the x-direction. There is haptic value in: having thecorrelation or alignment of tactile feedback with finger/cursor motion;in some cases, alignment can boost the haptic signal-to-noise ratio. Forexample, moving the cursor right to left over icons or buttons may feelbetter and more like real buttons to the user when the feedback isdirected horizontally along the x-axis. Less power may be requiredoverall if the feedback is aligned with the cursor direction instead ofbeing omnidirectional or misaligned. In some cases, a weaker alignedhaptic effect may be more meaningful than a stronger misaligned effect.

The touchpad surface with enhanced texture moves relative to a fixedsurrounding surface with enhanced texture. The enhanced texture is morerough, corrugated, or otherwise textured, allowing a stronger usercontact.

In some other embodiments, the touchpad surface can be comprised ofinterdigitated surface features that move relative to each other in x-and/or y-directions. For example, two halves of a touchpad can be drivenby actuator(s) to move relative to each other.

In other embodiments, other actuators can be used to move the touchpad,touchscreen, or other touch device in the z-direction. For example,piezo-electric actuators, voice coil actuators, or moving magnetactuators can be directly coupled to the touchpad or touchscreen toprovide direct motion of the touch surface. Piezo-electric actuators aredescribed with reference to copending patent application Ser. No.09/487,737. Also, the touchpad surface can be comprised of a fixedtactile surface and a reference surface, where the reference surface candisplaced along the z-axis with respect to the fixed tactile surface.

FIGS. 15 a and 15 b are perspective views of the top side and bottomside, respectively, of a different embodiment of a novel “flat-E”actuator 360 for use in translating a touchpad. FIG. 15 c is a side viewof the actuator 360. Actuator 360 is designed to be very flat and thusmay be more appropriate to function within a flat assembly that can beinherently part of the touchpad, touchscreen, or other similar inputdevice. “E-core” actuator topology provides an excellent actuator usingminimal magnet material and delivers good force and bandwidth. Onedisadvantage of the moving magnet actuator is the large depth required(“E” core ferromagnetic piece width can be traded for height to someextent, perhaps reducing the overall depth of the actuator).

Actuator 360 presents a inventive embodiment of an “E” core that can beused to translate the touchpad (or alternatively to translate a separatesurface, as in the embodiments of FIGS. 9-14). A folded over, flat 3-Dembodiment, shown in FIGS. 15 a-15 b, that may behave substantially likea 2-D case, but with more leakage and non uniform flux at the poles.

Actuator 360 includes a ferromagnetic piece 362 shaped as an “E”, whichcan be made of a metal such as a ferrous metal or carbon steel plate,and can be a single piece of metal or a lamination. A coil 364 of wireis wound about the central pole of the “E” of the ferromagnetic piece362. A floating plastic cage 368 can be positioned on the ferromagneticpiece 362 and can include two or more rollers 370 positioned inapertures in the cage and oriented so that the rollers roll about axesparallel to the axis passing through the coil 364 about which the coilis wound. The cage can be plastic and is floating, i.e. unattached toother components, to allow the rollers to roll. A two-pole magnet 366 ispositioned above the poles of the ferromagnetic piece 362 and cage 368so that there is an air gap between magnet and ferromagnetic piece. Themagnet 366 is coupled to the underside (in the orientation of thefigures; other orientations are possible) of a backing steel piece 372which is positioned on top of and contacting the rollers 370. Therollers thus set the nominal magnetic gap between the magnet and theferromagnetic piece 362. The backing steel piece 372 can be rigidlycoupled to the touchpad 373, as shown in FIG. 15 d, so that thetouchpad, steel piece 372, and magnet 366 can translate relative to theferromagnetic piece 362. For example, the magnet may in some embodimentsbe a two pole bonded neodymium wafer, and the steel parts may be stampedfrom single sheets about 1 mm thick. Additional rollers or foam can beused to support the end of the ferromagnetic piece opposite the magnet366. The magnet, cage, and backing piece are located to the side of the“E” poles rather than at the front edge as in other E-core typeactuators; this allows the actuator of the present invention to be madevery flat for laptop and other portable device applications.

In operation, an electrical current is flowed through the coil 364,which causes magnetic flux to flow through the ferromagnetic piece inthe direction of arrows 374. In reaction; the steel plate 372 moves in adirection along the axis indicated by arrow 376 (the direction isdependent on the direction of the current in the coil). The rollers 370rotate to allow the steel plate 372 and magnet 366 to translate relativeto the ferromagnetic piece 362. The floating cage 368 keeps the rollersfrom moving in undesired directions as they rotate. Also, the magneticattractive normal forces which occur between ferromagnetic piece 362 andmagnet 366 are reacted with the rollers 370. Other Flat-E relatedembodiments can include flexure and knife-edge suspensions to react(allow motion from) magnetic normal forces.

The flat E actuator embodiments described herein can be used totranslate the touchpad (or touchscreen) or a separate surface memberabove or to the side of the touchpad. For example, two flat E actuatorscan be used in a configuration similar to that of FIG. 9 to drive thetouchpad or surface member in two axes, x and y.

The actuator 360 can be made very thin in comparison with otheractuators, e.g. the assembly can be made approximately 3 or 4 mm thick,less than half as thick as other “E” core actuators. The magneticsdesign can be iterated for optimal performance. Linearity and detentforces can be traded for thickness.

Advantages include a planar, thin geometry, which is suitable forlaptops, PDA, and other portable devices. The moving magnet approachdoes not require a large air gap so it may be more attractive for laptophaptic feedback. An “E” core prototype was 10 mm×20 mm×8 mm and issmaller than most DC motors with equivalent force and power consumption.Furthermore, it is a direct drive configuration, so no transmission isrequired between actuator and touchpad. Efficient, low cost, and easy tomanufacture components allow the actuator to be produced cheaply. Theactuator is simple to integrate with existing touchpad PCB's andmodules. One disadvantage is that magnetic attractive normal forcesexist, which may necessitate a suspension. Rollers and/or flexure andknife edge suspensions can be used in some embodiments to react magneticnormal forces.

The actuator 360 generally provides good bandwidth. Larger (e.g., >1 mm)displacements can be achieved. Those embodiments employing foam tosupport the opposite end of the ferromagnetic piece have a return springhaving a low spring constant, mostly from the foam suspension operatedin shear mode. Audible noise may also be reduced by using the foamand/or rollers. While the haptic performance is good, the displacementof the surface is small enough so that when the user is moving a fingerover the touchpad to move the cursor over the desktop, the surfacedisplacement does not noticeably affect the cursor motion.

FIGS. 16 a and 16 b are perspective views of the top side and bottomsides of another embodiment 380 of the “flat-E” actuator of FIGS. 15a-15 c. A ferromagnetic piece 382 (or a lamination, in otherembodiments) includes an approximate “E” structure and has a coil 384wound around the E center pole 385. A two-pole magnet 386 is positionedacross the E center pole 385 such that a gap is provided betweenferromagnetic piece 382 and magnet, similarly to the embodiment 360. Ametal plate 388 (e.g., steel) is coupled to magnet 386 and is providedparallel to the ferromagnetic piece and magnet. A cage 390 can beprovided as the middle layer, where rollers 389 (shown as dashed lines)can be positioned within apertures in the cage 390 and allow the plate388 to slide laterally with respect to the ferromagnetic piece andmagnet. A touchpad or touchscreen (not shown) can be rigidly coupled tothe top of plate 388, with piece 382 grounded. In alternate embodiments,the touchpad or touch screen can be coupled to the piece 382 with plate388 grounded.

Embodiment 380 also includes a flexible suspension, which can be coupledto the middle layer plastic cage 390 and can include two linkages 392that are thus effectively coupled between the steel plate 388 and theferromagnetic piece 382. The linkages 392 contact the steel plate 388 atends 394 and are coupled to the cage layer 390 at ends 396 (or moldedwith the cage layer as a single plastic piece). Each linkage includes athinner portion 398 and a thicker portion 400.

In operation, a current is flowed through coil 384 and the magneticforces resulting from the current and magnet 386 cause the plate 388(and the touchpad) to move as indicated by axis 402. The suspensionincluding linkages 392 prevents the plate 388 from skewing due tomagnetic normal forces and any other forces. Each linkage 392 flexes toaccommodate the motion of the plate 388, where the thinner members 398flex first, and the thicker members 400 flex if the limits of flex arereached for members 398. The thinner-thicker structure allows springcentering to operate until the thicker (stiffer) beams are engaged,which provide a softer feeling stop to motion. The final limit to motionis caused by either of the stops 404 hitting the inner edge of the plate388.

The flexible suspension described above effectively allows lateraldesired motion of the plate and touchpad, but prevent motion in anyother direction. This creates a much more stable motion of the plate 388and does not allow the plate 388 to drift in its position over time.Furthermore, the suspension provides a desirable spring centering forceon the plate 388 and touchpad, allowing the touchpad to move to thecenter of its range of motion when the user stops touching and forcingthe touchpad.

FIGS. 17 a-17 g are views illustrating another flat-E actuator touchpadembodiment 420 that miniaturizes this type of actuator and providesfabricated surface mount devices that take advantage of existing leadframe and over molding manufacturing technologies. Such small scaledevices can be wave soldered onto the touchpad module and can work inparallel to provide suitable stroke and force for touchpad translation(or for z-axis forces in alternate embodiments).

FIGS. 17 a-17 c illustrate a top view of a PCB 422 which includesmultiple Flat-E actuators 424. An actuator 424 can be positioned at eachcomer of the PCB 422 as shown. More or less actuators than shown canalternatively be placed in other configurations. The use of multipleactuators 422 can provide greater magnitude forces and allow eachactuator 422 to have a lower force output and cost. In one embodiment,the PCB 422 is a separate PCB that is grounded to the housing of thelaptop. The touchpad (e.g., including its own PCB different from PCB422) is then coupled to the moving portions of the actuators, e.g., tothe pads 426 shown in FIG. 17 a. In another embodiment, the PCB 422 isthe touchpad, and the moving portions of the actuators are coupled to agrounded surface in the laptop, such as the housing. In such anembodiment, the actuators 424 can be hidden from the user by a lip ofhousing that extends around the perimeter of the touchpad, leaving thecenter area of the PCB 422 exposed to the user.

FIG. 17 d is a side elevational view of one end of a PCB 422, separatefrom the touchpad, that includes the flat-E actuators 424. Thetouchpad/PCB member 428 is coupled to the moving portions 430 of theactuators 424.

FIG. 17 e is a perspective view illustrating one embodiment of theunderside of the PCB 422 shown in FIG. 17 a, where the flat-E actuators424 have been surface mounted to the underside of the PCB 422. This canbe done as “hand-placed” components, or preferably using automaticsurface mount technology placement equipment. The “E” ferromagneticpiece 432 can be grounded to the PCB 422 so that the magnet and steelbacking plate of the actuator move.

FIGS. 17 f and 17 g are perspective views illustrating top and bottomviews, respectively, of the flat-E actuator 424 which has 3 poles andcan operate similarly to the flat-E actuators described above.Ferromagnetic piece 432 is shaped like an “E” and has a coil 434 wrappedabout the center pole. Flexures 436 allow the magnet 438 and steelbacking plate 440 to move relative to the ferromagnetic piece 432 andcoil 434. The touchpad (not shown) can be coupled to the steel backingpiece 440 and the E-laminate piece 432/coil 434 can be grounded, as inthe embodiments of FIGS. 17 a-17 e. Alternatively, the backing piece.440 and magnet 438 can be grounded and the touchpad can be coupled to amoving ferromagnetic piece 432.

A flat-E actuator as described above can be used to translate touchpadmodules or palm surfaces directly. In the described embodiments, thetotal thickness of the flat-E actuator can be about 3 mm or less. Flat-Emagnetic assemblies that can be integrated into the an existing touchpadproduct line represent a preferred embodiment in terms of size,manufacturability and economy of scale.

In other embodiments, other moving magnet actuator designs, such asdescribed in copending application Ser. No. 09/608,130, and other voicecoil actuator designs, such as described in U.S. Pat. Nos. 6,166,723 and6,100,874, can be used; these applications and patents are incorporatedherein by reference in their entirety. Voice coil actuators may bethicker since the coil is positioned in a relatively large magnetic gap.Moving magnet actuators typically have smaller inherent air gaps.

In other embodiments, other types of input surfaces or display screenscan be similarly translated using any of the actuators described herein.For example, a clear surface such as the input sensing device(s)covering a display screen of a personal digital assistant (PDA) or atouch screen on a monitor or CRT, can be similarly translated in the Xand/or Y directions (parallel to the screen surface) to provide hapticfeedback. One application for such clear screen translation is ATMmachines, where the user typically inputs information on a touch screen.Haptic feedback can make such input more accessible and easy for peoplewith below-average vision. Haptic feedback can indicate when the user'sfinger is over a graphically-displayed button, or can identifyparticular displayed buttons with different haptic sensations. This canbe useful in many ATM applications since there is not a cursor that ismoved; haptic feedback can thus be useful to indicate to the user that abutton has been pressed, e.g. a small vibration is output when a buttonis activated. Haptic feedback may also assist users in noisyenvironments, such as in areas with high vehicular traffic, where soundmay not be easily heard by the user.

The embodiments described herein can also provide haptic feedback in anembodiment where the user is using a stylus or other object to inputdata on the touchpad, touch screen, or input area. The haptic sensationscan be transmitted to the user from the touchpad (or other movingsurface) and through the stylus or other object.

Other Features

A human factor issue related to haptic feedback in some embodiments mayinclude force overload protection. Ideally, for non-inertial feedbackactuators and transmission designs such as the translating surfaces anddifferential surfaces, it is desired for the actuator to produce largeforces with fidelity regardless of the load on the actuator or theposition within the actuator travel. Put another way, the finger or handof the user should not move the actuator against a limit or reach an endof travel .condition where half of a vibration cycle is attenuated. Forthis reason, it is desirable to design actuator and transmissionmechanisms that are inherently decoupled from the user loading. Anexample of this would be an E-core actuator with very high springcentering provided by a stiff suspension, as in the embodiment of FIG.16 a-16 b. A forceful actuator can overcome this spring force easily,and the forces of a finger dragging on a touchpad surface are a smallpercentage of full scale actuator output. A weaker actuator may requirea more compliant suspension, and this would allow the user interactionto interfere with oscillations and create non-linear output.

Another human-factor-related issue with haptic feedback in someembodiments can be audibility. The use of palm rest surfaces andinertial actuator assemblies, for example, causes sound that is theunavoidable side effect of a haptic sounding board. Loaded surfaces,such as when the user is touching the housing or touchpad, radiate soundpoorly, and still transmit forces quite well. Thus, in some embodiments,a load measuring device can be used to determine when the user's handsare present on moving surfaces to allow forces to be output only whensuch hands are present.

To save costs when providing haptic functionality to a laptop touchpador other similar input device, the existing sound electronics within thelaptop, PDA, or other device can be utilized in some embodiments. Forexample, the existing sound analog output (e.g. digital-to-analogconverter) and the sound power amplifiers can drive the actuator usedfor haptic feedback for the touchpad or other laptop component asdescribed above, without having to add an additional microprocessorand/or additional power electronics. A notch filter or other pickofffrom the sound signal can be used to provide the haptic feedback signal.For example, haptic effect control signals can be provided in theinaudible range of the sound spectrum and filtered so that these controlsignals can be provided to the haptic actuator, while the remainder ofthe signal in the audible range is routed to the audio speakers of thelaptop. Or, dedicated signals that are outside the audible range and notincluded with audio signals can be filtered or routed to control thehaptic feedback actuator(s).

Furthermore, existing software on many laptops tracks the battery powerfor the laptop to indicate power level, warn the user, or shutoff thelaptop to conserve battery power. This tracking software can be tappedinto for haptic feedback applications. For example, if battery powergets below a certain level, the haptic feedback software routines canscale down or even turn off the output forces to the user. This can beaccomplished by dropping the magnitude of the forces, or by reducing thetypes or number of graphical objects in the GUI that have haptic effectsassociated with them. This can also be accomplished by shortening theduration of haptic effects, e.g. effects that are normally 50 ms can bereduced to 40 ms, etc. Also, a combination of such methods can be used.Finally, some laptop computers have different settings, such as highpower, medium power, and low power, which a user can select according tohis or her needs, e.g. lower power setting allows the batteries to lastlonger. The haptic feedback control can link into the setting and begoverned by this setting as well. For example, if the user selects lowpower mode, the haptic feedback controller can adapt as described aboveto reduce power requirements of the haptic effects.

FIG. 18 is a top elevational view of a touchpad 450 of the presentinvention. Touchpad 450 can in some embodiments be used simply as apositioning device, where the entire area of the touchpad providescursor control. In other embodiments, different regions of the pad canbe designated for different functions. In some of these regionembodiments, each region can be provided with an actuator located underthe region or otherwise physically associated with the region, whileother region embodiments may use a single actuator that imparts forceson the entire touchpad 450. In the embodiment shown, a central cursorcontrol region 452 can be used to position a cursor or viewpointdisplayed by the laptop computer or other device.

The cursor control region of a touchpad can cause forces to be output onthe touchpad based on interactions of the controlled cursor with thegraphical environment and/or events in that environment. The user movesa finger or other object within region 452, for example, tocorrespondingly move the cursor 20. Forces are preferably associatedwith the interactions of the cursor with displayed graphical objects.For example, a jolt or “pulse” sensation can be output, which is asingle impulse of force that quickly rises to the desired magnitude andthen is turned off or quickly decays back to zero or small magnitude.The touchpad 450 can be jolted in one direction or as an oscillation inthe z-axis or other axis inertially in the inertial haptic feedbackembodiments, or the touchpad can be translated in one direction oroscillated one or more times to provide the pulse. A vibration sensationcan also be output, which is a time-varying force that is typicallyperiodic. The vibration can cause the touchpad 450 or portions thereofto oscillate back and forth multiple times, and can be out put by a hostor local microprocessor to simulate a particular effect that isoccurring in a host application.

Another type of force sensation that can be output on the touchpad is atexture force. This type of force is similar to a pulse force, butdepends on the position of the user's finger on the area of the touchpadand/or on the location of the cursor in a graphical environment. Thus,texture bumps can be output depending on whether the cursor has movedover a location of a bump in a graphical object. This type of force isspatially-dependent, i.e. a force is output depending on the location ofthe cursor as it moves over a designated textured area; when the cursoris positioned between “bumps” of the texture, no force is output, andwhen the cursor moves over a bump, a force is output. This can beachieved by host control (e.g., the host sends the pulse signals as thecursor is dragged over the grating). In some embodiments, a separatetouchpad microprocessor can be dedicated for haptic feedback with thetouchpad, and the texture effect and be achieved using local control(e.g., the host sends a high level command with texture parameters andthe sensation is directly controlled by the touchpad processor). Inother cases a texture can be performed by presenting a vibration to auser, the vibration being dependent upon the current velocity of theuser's finger (or other object) on the touchpad. When the finger isstationary, the vibration is deactivated; as the finger is moved faster,the frequency and magnitude of the vibration is increased. Thissensation can be controlled locally by the touchpad processor (ifpresent), or be controlled by the host. Such texture sensations aredescribed in copending application Ser. No. 09/504,201, which isincorporated herein by reference. Other spatial force sensations canalso be output. In addition, any of the described force sensationsherein can be output simultaneously or otherwise combined as desired.

Different types of graphical objects can be associated with hapticsensations. Haptic sensations can output on the touchpad based oninteraction between a cursor and a window, menu, icon, web page link,etc. For example, a “bump” or pulse can be output on the touchpad tosignal the user of the location of the cursor when the cursor is movedover a border of a window. In other related interactions, when a ratecontrol or scrolling function is performed with the touchpad (throughuse of the cursor), sensations can be output related to the rate controlfunctions. Furthermore, the magnitude of output forces on the touchpadcan depend on the event or interaction in the graphical environment,including user-independent events. These force sensations can also beused in games or simulations. These and other haptic sensations aredescribed in U.S. Pat. No. 6,211,861 and copending patent applicationSer. No. 09/585,741, both incorporated herein by reference. Othercontrol devices or grips that can include a touchpad of the presentinvention in its housing include a gamepad, mouse or trackball devicefor manipulating a cursor or other graphical objects in acomputer-generated environment; or a pressure sphere or the like.

Some forms of touchpads and touchscreens allow the amount of pressurethe user is exerting on the touchpad to be sensed. This allows a varietyof haptic sensations to be determined based at least in part on thesensed pressure. For example, a periodic vibration can be output havinga frequency that depends on the sensed pressure. Or, the gain(magnitude) of output haptic sensations can be adjusted based on thesensed pressure. Those users that always tend to use the touchpad withmore pressure can be allowed to select an automatic magnitude increasethat would be in effect constantly.

Other embodiments of touchpads and touchscreens allow the user to enter“gestures” or shortcuts by tracing a symbol on the cursor control regionor other region, which is recognized as a command or data by aprocessor. Haptic sensations can be associated with or dependent onparticular gestures. For example, a confirmation of modes can beconveyed haptically with a particular haptic sensation when a modeconfirmation gesture is recognized. Characters recognized from gesturesalso may each have a particular haptic sensation associated with them.In most touchpad embodiments, a user can select a graphical object ormenu item by “tapping” the touchpad. Some touchpads may recognize a“tap-and-a-half” or double tap, which is the user doing a tap and thenagain touching the pad and maintaining the finger or object on the padwhile moving the finger. For example, such a gesture can provide a“drag” mode in which objects may be moved with the cursor. When the useris in such a drag mode, a vibration or other haptic sensation can beoutput to indicate to the user that this mode is active.

As stated above, the touchpad 450 can also be provided with differentcontrol regions that provide separate input from the main cursor controlregion 452. In some embodiments, the different regions can be physicallymarked with lines, borders, or textures on the surface of the touchpad450 (and/or sounds from the computer 10) so that the user can visually,audibly, and/or or tactilely tell which region he or she is contactingon the touchpad.

For example, scroll or rate control regions 454 a and 454 b can be usedto provide input to perform a rate control task, such as scrollingdocuments, adjusting a value (such as audio volume, speaker balance,monitor display brightness, etc.), or panning/tilting the view in a gameor simulation. Region 454 a can be used by placing a finger (or otherobject) within the region, where the upper portion of the region willincrease the value, scroll up, etc., and the lower portion of the regionwill decrease the value, scroll down, etc. In embodiments that can readthe amount of pressure placed on the touchpad, the amount of pressurecan directly control the rate of adjustment; e.g., a greater pressurewill cause a document to scroll faster. The region 454 b can similarlybe used for horizontal (left/right) scrolling or rate control adjustmentof a different value, view, etc.

Particular haptic effects can be associated with the control regions 454a and 454 b. For example, when using the rate control region 454 a or454 b, a vibration of a particular frequency can be output on thetouchpad. In those embodiments having multiple actuators, an actuatorplaced directly under the region 454 a or 454 b can be activated toprovide a more localized tactile sensation for the “active” (currentlyused) region. As a portion of a region 454 is pressed for rate control,pulses can be output on the touchpad (or region of the touchpad) toindicate when a page has scroll by, a particular value has passed, etc.A vibration can also be continually output while the user contacts theregion 454 a or 454 b.

Other regions 456 can also be positioned on the touchpad 450. Forexample, each of regions 456 can be a small rectangular area, like abutton, which the user can point to in order to initiate a functionassociated with the pointed-to region. The regions 456 can initiate suchcomputer functions as running a program, opening or closing a window,going “forward” or “back” in a queue of web pages in a web browser,powering the computer 10 or initiating a “sleep” mode, checking mail,firing a gun in a game, cutting or pasting data from a buffer, saving afile to a storage device, selecting a font, etc. The regions 456 canduplicate functions and buttons provided in an application program orprovide new, different functions.

Similarly to regions 454, the regions 456 an each be associated withhaptic sensations; for example, a region 456 can provide a pulsesensation when it has been selected by the user, providing instantfeedback that the function has been selected. For example, a hapticsensation such as a pulse can be output when the user “taps” a finger orobject on a region 456, 452, or 454 to make a selection. Similar tophysical analog buttons that provide a range of output based on how farthe button is pushed, one or more regions 456 can be an analog-likebutton by providing a proportional, stepped, or analog output based onthe pressure the user is exerting on the touchpad.

Furthermore, the same types of regions can be associated withsimilar-feeling haptic sensations. For example, each word-processorrelated region 456 can, when pointed to, cause a pulse of a particularstrength, while each game-related region 456 can provide a pulse ofdifferent strength or a vibration. Furthermore, when the user moves thepointing object from one region 454 or 456 to another, a hapticsensation (such as a pulse) can be output on the touchpad 450 to signifythat a region border has been crossed For example, a high frequencyvibration which quickly decays to zero magnitude can be output when thepointing object enters a designated region. This can be valuable sinceit provides an indication of the borders to the regions 454 and 456which the user would not otherwise know. This also allows regionreconfiguration of size and/or location and allows the user to quicklylearn the new layout haptically. Regions can also be associated with“enclosures” which define areas in a graphical environment and thedifferent haptic sensations which are output when the cursor enters,exits, and is moved within the enclosure and the particular bordershaving such haptic associations.

In addition, the regions are preferably programmable in size and shapeas well as in the function with which they are associated. Thus, thefunctions for regions 456 can change based on an active applicationprogram in the graphical environment and/or based on user preferencesinput to and/or stored on the computer 10. Preferably, the size andlocation of each of the regions can be adjusted by the user or by anapplication program, and any or all of the regions can be completelyremoved if desired. Furthermore, the user is preferably able to assignparticular haptic sensations to particular areas or types of areas basedon types of functions associated with those areas, as desired. Differenthaptic sensations can be designed in a tool such as Immersion Studio™available from Immersion Corp. of San Jose, Calif.

It should be noted that the regions 454 and 456 need not be physicalregions of the touchpad 450. That is, the entire touchpad surface needmerely provide coordinates of user contact to the processor of thecomputer and software on the computer can designate where differentregions are located. The computer can interpret the coordinates and,based on the location of the user contact, can interpret the touchpadinput signal as a cursor control signal or a different type of signal,such as rate control, button function, etc. (e.g. a driver programcan,provide this interpreting function if desired). A local touchpadmicroprocessor, if present, may alternatively interpret the functionassociated with the user contact location and report appropriate signalor data to the host processor (such as position coordinates or a buttonsignal), thus keeping the host processor or software ignorant of thelower level processing. In other embodiments, the touchpad 450 can bephysically designed to output different signals to the computer based ondifferent regions physically marked on the touchpad surface that arecontacted by the user; e.g. each region can be sensed by a differentsensor or sensor array.

Any of those embodiments described herein which provide haptic feedbackto the finger or object of the user that contacts the touchpad ortouchscreen may be used with the regions of touchpad 450.

While this invention has been described in terms of several preferredembodiments, it is contemplated that alterations, permutations, andequivalents thereof will become apparent to those skilled in the artupon a reading of the specification and study of the drawings. Forexample, many of the features described in one embodiment can be usedinterchangeably with other embodiments. Furthermore, certain terminologyhas been used for the purposes of descriptive clarity, and not to limitthe present invention.

1-58. (cancelled).
 59. An apparatus, comprising: a substantially-planarcontact surface; a piezoelectric member including a metal diaphragmdisposed between the substantially-planar contact surface and a ground;and a spacer having a mass disposed between the substantially-planarcontact surface and the ground and adjacent to the metal diaphragm, themass of the spacer configured to cause the piezoelectric actuator tooscillate at a predetermined frequency to provide haptic feedback. 60.The apparatus of claim 59, wherein the haptic feedback is in response toan input associated with the substantially-planar contact surface. 61.The apparatus of claim 60, further comprising a processor incommunication with the substantially-planar contact surface and thepiezoelectric actuator.
 62. The apparatus of claim 59, wherein thepredetermined frequency is associated with a resonant frequency of theapparatus.
 63. The apparatus of claim 59, wherein the predeterminedfrequency is associated with a modulation of a carrier frequency of thepiezoelectric actuator.
 64. The apparatus of claim 59, wherein thesubstantially-planar contact surface is coupled to the ground via aspring element.
 65. The apparatus of claim 64, wherein the predeterminedfrequency is associated with a spring constant of the spring element.66. The apparatus of claim 59, wherein the spacer is coupled to theground via a spring element.
 67. The apparatus of claim 66, wherein thepredetermined frequency is associated with a spring constant of thespring element.
 68. The apparatus of claim 59, wherein the groundcomprises a contact pad.
 69. The apparatus of claim 59, wherein theground comprises a housing.
 70. The apparatus of claim 69, wherein thehousing is associated with a handheld device.
 71. The apparatus of claim70, wherein the handheld device comprises one of a personal digitalassistant (PDA), a cellular phone, and an electronic book.
 72. Theapparatus of claim 59, wherein a touch screen comprises thesubstantially-planar contact surface.
 73. The apparatus of claim 59,wherein a touchpad comprises the substantially-planar contact surface.74. The apparatus of claim 59, wherein the substantially-planar contactsurface is textured.
 75. An apparatus, comprising: asubstantially-planar contact surface; a piezoelectric member coupled tothe substantially-planar contact surface; and a spring elementconfigured to couple the substantially-planar contact surface to aground, a spring constant of the spring element configured to cause thepiezoelectric actuator to oscillate at a predetermined frequency toprovide haptic feedback.
 76. The apparatus of claim 75, wherein thehaptic feedback is in response to an input associated with thesubstantially-planar contact surface.
 77. The apparatus of claim 75,wherein the predetermined frequency is associated with a resonantfrequency of the apparatus.
 78. The apparatus of claim 75, wherein thepredetermined frequency is associated with a modulation of a carrierfrequency of the piezoelectric actuator.
 79. The apparatus of claim 75,further comprising a spacer disposed between the substantially-planarcontact surface and the ground, the predetermined frequency beingassociated with a mass of the spacer.
 80. The apparatus of claim 75,wherein the ground comprises a housing.
 81. The apparatus of claim 80,wherein the housing is associated with a handheld device.
 82. Theapparatus of claim 81, wherein a touch screen comprises thesubstantially-planar contact surface.
 83. The apparatus of claim 75,wherein a touchpad comprises the substantially-planar contact surface.84. The apparatus of claim 75, wherein the substantially-planar contactsurface is textured.
 85. An apparatus, comprising: a ferromagneticelement having a center pole disposed between two side poles, the centerpole being associated with a coil; at least one magnet configured to bein magnetic communication with the center pole and the side poles; asubstantially-planar contact surface coupled to the at least one magnet;and a coupling means disposed between the substantially-planar contactsurface and the ferromagnetic element, the coupling means configured tofacilitate a relative motion between the substantially-planar contactsurface along with the at least one magnet and the ferromagnetic elementwhen the coil carries a current.
 86. An apparatus of claim 85, whereinthe coupling means comprises a plurality of rollers.
 87. An apparatus ofclaim 86, wherein the rollers are coupled to a cage member.
 88. Anapparatus of claim 85, wherein the substantially-planar contact surfaceis coupled to the at least one magnet via a backing plate.
 89. Anapparatus of claim 88, wherein the backing plate comprise steel.
 90. Anapparatus of claim 88, further comprising a flexure element disposedbetween the backing plate and the ferromagnetic element, the flexureelement configured to provide a spring centering force between thebacking plate and the ferromagnetic element.
 91. An apparatus of claim85, wherein a touch screen comprises the substantially-planar contactsurface.
 92. An apparatus of claim 85, wherein the relative motioncorresponds with an input associated with the substantially-planarcontact surface.